The phylogenetics of Teleosauroidea (Crocodylomorpha, Thalattosuchia) and implications for their ecology and evolution

Teleosauroidea was a clade of ancient crocodylomorphs that were a key element of coastal marine environments during the Jurassic. Despite a 300-year research history and a recent renaissance in the study of their morphology and taxonomy, macroevolutionary studies of teleosauroids are currently limited by our poor understanding of their phylogenetic interrelationships. One major problem is the genus Steneosaurus, a wastebasket taxon recovered as paraphyletic or polyphyletic in phylogenetic analyses. We constructed a newly updated phylogenetic data matrix containing 153 taxa (27 teleosauroids, eight of which were newly added) and 502 characters, which we analysed under maximum parsimony using TNT 1.5 (weighted and unweighted analyses) and Bayesian inference using MrBayes v3.2.6 (standard, gamma and variation). The resulting topologies were then analysed to generate comprehensive higher-level phylogenetic hypotheses of teleosauroids and shed light on species-level interrelationships within the clade. The results from our parsimony and Bayesian analyses are largely consistent. Two large subclades within Teleosauroidea are recovered, and they are morphologically, ecologically and biogeographically distinct from one another. Based on comparative anatomical and phylogenetic results, we propose the following major taxonomic revisions to Teleosauroidea: (1) redefining Teleosauridae; (2) introducing one new family and three new subfamilies; (3) the resurrection of three historical genera; and (4) erecting seven new generic names and one new species name. The phylogeny infers that the Laurasian subclade was more phenotypically plastic overall than the Sub-Boreal-Gondwanan subclade. The proposed phylogeny shows that teleosauroids were more diverse than previously thought, in terms of morphology, ecology, dispersal and abundance, and that they represented some of the most successful crocodylomorphs during the Jurassic.

While teleosauroid skeletal and dental morphology has been well documented from the 18th Century to present (Chapman, 1758;Cuvier, 1824;Von Meyer, 1837;Eudes-Deslongchamps, 1867;Blake, 1876;Andrews, 1909Andrews, , 1913Westphal, 1961Westphal, , 1962Johnson et al., 2017;Johnson, Young & Brusatte, 2019;Foffa et al., 2019;Sachs et al., 2019a), the evolutionary relationships of these crocodylomorphs are poorly understood and little studied. This is problematic, as phylogenies are crucial when evaluating evolutionary changes throughout time (Purvis, Gittleman & Brooks, 2005;Mishra & Thines, 2014). One of the major problems in teleosauroid systematics is the nomenclatural nightmare that is the taxon Steneosaurus. Widespread taxonomic lumping has seen this genus become a 'wastebasket' for a multitude of species. The validity of Steneosaurus has recently been called into question (Jouve et al., 2017;Johnson, Young & Brusatte, 2020) as the type specimen of the type species, Steneosaurus rostromajor Geoffroy Saint-Hilaire, 1825 (MNHN.RJN 134c-d), has rarely been referenced or figured in the literature since its preliminary descriptions by Cuvier (1800Cuvier ( , 1808Cuvier ( , 1812Cuvier ( , 1824 and Geoffroy Saint-Hilaire (1825. Another problematic issue reinforced during the 20th Century (Andrews, 1909(Andrews, , 1913 is the contention that while there are noticeable differences between the skulls of teleosauroid species, the postcranial skeleton only shows superficial differences. This led to the assumption that teleosauroids must have lived in similar habitats with a conservative body plan (Andrews, 1913;Buffetaut, 1982). However, recent studies Johnson et al., 2017;Foffa et al., 2019;Martin et al., 2016Martin et al., , 2019Wilberg, Turner & Brochu, 2019) have begun to dispute this notion, showing, in terms of postcranial anatomy and palaeoenvironment, that teleosauroids were more diverse than originally thought.
Herein we present an in-depth, comprehensive phylogenetic study of Teleosauroidea, using the most recently updated crocodylomorph dataset. We will: (1) explore the historical background of teleosauroid phylogenetics; (2) discuss the materials and phylogenetic methods used; (3) provide a novel, comprehensive taxonomic layout of Teleosauroidea; (4) list detailed descriptions of both newly scored and morphologically important characters; (5) evaluate the results of the phylogenetic analyses; and (6) elucidate what this new phylogeny implies about teleosauroid ecomorphological and distributional patterns. The leisurely rise of teleosauroid phylogenetics-post-2010 Bronzati, Montefeltro & Langer (2012) presented an in-depth crocodylomorph supertree and included 19 teleosauroid species in their analysis; however, the Chinese teleosaurid (IVPP V 10098) was attributed to the metriorhynchoid Peipehsuchus; S. edwardsi, and Steneosaurus durobrivensis Andrews, 1909 (which is now considered a subjective junior synonym of S. edwardsi; see Johnson et al. (2015)) were treated as separate taxa; and Steneosaurus pictaviensis Vignaud, 1998, was included (which is a subjective junior synonym of S. leedsi; see below). Several key taxa were also absent in the analysis (e.g. Myc. nasutus, S. obtusidens, Machimosaurus mosae Sauvage & Liénard, 1879).
In addition, Bronzati, Montefeltro & Langer (2012) searched for their source trees on Web of Science, other Internet search engines and published references, synthesizing published phylogenies and thus not personally examining the specimens. The result was a major polytomy of Teleosauroidea as a whole, with 'Mystriosaurus' and Pl. multiscrobiculatus unresolved at the base. Wilberg (2015a) devised an updated crocodylomorph matrix (referred herein as the W matrix) which included nine teleosauroid taxa (S. brevior; Steneosaurus brevidens Phillips, 1871; 'Teleosaurus'; Mac. hugii; S. leedsi; S. durobrivensis; Pl. multiscrobiculatus; S. bollensis; and Peipehsuchus [again considered a teleosauroid]). The strict consensus topology produced 566 MPTs and 1,649 steps (CI = 0.312; RI = 0.703) and a monophyletic teleosauroid clade, which continued to be stable regardless of different constraints placed on thalattosuchians as a whole (Wilberg, 2015a). This is somewhat similar to the results seen in follow-up studies by Wilberg (2015b) (Fig. 1C), Wilberg (2017) and Wilberg, Turner & Brochu (2019), and these produced comparable results to the recently updated Hastings+Young matrices (see below). However, there is one major change from Wilberg (2015a) to the updated results in Wilberg (2015b) and Wilberg, Turner & Brochu (2019): Pel. typus is now moved to the base of Metriorhynchoidea.
Recently, several new re-descriptions of teleosauroid taxa have begun to investigate crocodylomorph, notably thalattosuchian, phylogenetics (Foffa et al., 2019;Johnson, Young & Brusatte, 2019;Sachs et al., 2019a). In particular, a dataset known as the Hastings +Young (H+Y) dataset is being continuously updated to assess these evolutionary relationships. In 2016, Hastings and Young combined their respective crocodylomorph matrices to create this dataset, which acted as the foundation for the Crocodylomorph SuperMatrix Project. Ristevski et al. (2018), focusing on the interrelationhsips within goniopholidids, ran the first comprehensive version of this dataset, which included 14 thalattosuchians and three teleosauroids (Pl. multiscrobiculatus, S. heberti and S. bollensis). Ősi et al. (2018), describing the metriorhynchoid Magyarosuchus fitosi, ran an updated version of the H+Y matrix with 140 OTUs (operational taxonomic units) for 454 characters, resulting in 84 MPTs with 1,477 steps. Fifteen teleosauroids were included and Teleosauroidea was recovered as a monophyletic group, with S. gracilirostris as the basal-most teleosauroid and two distinct subgroups. When re-describing 'S.' megarhinus, Foffa et al. (2019) used a slightly modified version of the H+Y dataset: 140 OTUs, 18 of these teleosauroid taxa, for 456 characters, producing 85 MPTs with 1,494 steps (CI = 0.414, RI = 0.841). The strict consensus topology was similar to that found in Ősi et al. (2018) (S. gracilirostris as the basal taxon, two distinct subgroups), but showed different positions of certain taxa, most notably Aeolodon priscus and 'Teleosaurus' (Bathysuchus) megarhinus. In Johnson, Young & Brusatte (2019) and Sachs et al. (2019a), subsequent versions of the H+Y dataset were used; the phylogenetic analyses included 19 and 18 teleosauroid taxa, respectively, both producing an overall similar appearance of Teleosauroidea as that of Ősi et al. (2018) and Foffa et al. (2019). The H+Y dataset used in Johnson, Young & Brusatte (2019)  Curiously, Martin et al. (2019) used Wilberg's (2015a) dataset, with no explanation as to why they did not use one of the more recent versions of the Wilberg dataset then published (Wilberg, 2015b, Wilberg, 2017, or the W dataset in Ősi et al., 2018) or the most currently updated H+Y matrix (provided in Foffa et al. (2019) at that time). The W dataset (Wilberg, 2015a) was also used in Martin et al. (2016), again with no clarification as to why an updated W dataset (Wilberg, 2015b) was not used. Out of 78 OTUs, only 24 thalattosuchians (14 teleosauroids) were included (Martin et al., 2019), with similar taxonomic concerns found in Mueller-Töwe's (2006) analysis. For example S. durobrivensis (= subjective junior synonym of S. edwardsi; Johnson et al., 2015) was treated as a distinct taxon, and many distinct species were excluded from the analysis. Machimosaurus buffetauti Young et al., 2015b (initially described as a valid taxon in ) was treated as Mac. hugii due to the monospecific hypothesis put forth in Martin & Vincent (2013) (for more information, see Foffa et al. (2019)). Furthermore, while I. potamosiamensis and Mac. hugii were coded in their entirety into the W matrix, three characters (174, 176 and 184) were altered from the original used by Wilberg (2015a), but only for the Chinese teleosauroid (IVPP V 10098) (Martin et al., 2019). Thus, the results (12 MPTs with 1666 steps) (Fig. 1E) were drastically different than those found in Wilberg (2015b), Young et al. (2016), Ristevski et al. (2018), Ősi et al. (2018), Foffa et al. (2019), Johnson, Young & Brusatte (2019) and Sachs et al. (2019a).

Objectives and taxonomic sample
Our phylogenetic analysis focused specifically on valid Teleosauroidea taxa, which range from the Early Jurassic (lower Toarcian, for example Steneosaurus gracilirostris) to the Early Cretaceous (Machimosaurus rex Fanti et al., 2016). The current dataset is a newly modified version of the H+Y dataset. It has since grown substantially over the past three years, with the addition of new taxa and characters. It was first presented in Ristevski et al. (2018) and has been updated subsequently since then (Ősi et al., 2018;Foffa et al., 2019;Johnson, Young & Brusatte, 2019;Sachs et al., 2019aSachs et al., , 2019b. Our taxonomic sample consisted of 153 crocodylomorph taxa (OTUs) with Postosuchus kirkpatricki Chatterjee, 1985 as the outgroup taxon. Eighty OTUs are thalattosuchians,

Methodology
Our dataset, which includes 153 OTUs and 502 characters, was analysed by conducting unweighted and weighted maximum parsimony analyses using TNT 1.5 Willi Hennig Society Edition (Goloboff, Farris & Nixon, 2008;Goloboff & Catalano, 2016), following previous iterations (Ősi et al., 2018;Foffa et al., 2019;Johnson, Young & Brusatte, 2019;Sachs et al., 2019aSachs et al., , 2019b. Our dataset was analysed as previously described in Foffa et al. (2019), Johnson, Young & Brusatte (2019) and Sachs et al. (2019aSachs et al. ( , 2019b. Specifically, memory settings were increased with General RAM set to 900 Mb and the maximum number of trees to be held set to 99,999. Cladogram space was searched by means of the 'New Technology search' option in TNT (Sectorial Search, Ratchet, Drift, and Tree fusing) with 1,000 random-addition replicates (RAS). The trees were then subjected to a Traditional Search, with 'tree bisection reconnection' (TBR) branch swapping, using 1,000 replications and 10 trees saved per replication. In addition, the default setting was increased for the iterations of each method (except for Tree fusing, which was kept at three rounds). In the Sectorial Search, 1,000 Drift cycles (for selections of above 75) were run, as well as 1,000 starts and fuse trees (for selections below 75) and 1,000 rounds of Consensus Sectorial Searches (CSSs) and Exclusive Sectorial Searches (XSSs). For Ratchet, the program used 1000 ratchet iterations set to stop the perturbation when 1,000 substitutions were made or 99% of the swapping was reached. Lastly, in Drift, the analysis included 1,000 Drift cycles set to stop the perturbation when 1,000 substitutions were made or 99% of the swapping was reached. The collapsing rule used was 50%, and Bremer support values of 10 were also computed which measure branch support and indicate the number of extra steps required for a clade to collapse (Bremer, 1988;Müller, 2004). In addition, a majority rules unweighted consensus (50% cut-off) was examined, as it summarizes a specific collection of MPTs (Holder, Sukumaran & Lewis, 2008). The analysis was run again using implied weighing (k = 12), with the 'New Technology search' options (Sectorial Search, Ratchet, Drift and Tree fusing) with the same settings as outlined above.
In addition, our dataset was also analysed under Bayesian inference using MrBayes v3.2.6 Ronquist & Huelsenbeck, 2003;Ronquist et al., 2012). While Bayesian methods are generally more popular when using molecular phylogenetics, they are becoming more common in morphological studies, including those involving fossil data (Lewis, 2001;Prieto-Márquez, 2010;Slater, 2013;Brusatte & Carr, 2016). We chose to run our dataset in MrBayes to compare its results with that of the unweighted and weighted topologies in TNT. The Markov (Mk) model of Lewis (2001) was used, with three different variations applied. The first was a generalized test, using the default setting of MrBayes: this is the simplest model, in that all substitutions have the same rate or involves equal rates of character change (rates = equal). The second involved a gamma parameter distribution with four rate categories (rates = gamma ngammacat = 4), which allows for differing rates of character change. The rates = gamma refers to gamma distribution rates across sites, and ngammacat sets the number of rate categories for the gamma distribution. The third involves a slightly different gamma parameter distribution (lset applyto = (1) coding = variable rates = gamma). This test specifies how characters are sampled, with variable indicating that only variable characters have the possibility of being sampled. In all three analyses, four chains were used and ran for 4,000,000 generations, sampled every 100 generations. Trees that were generated during the first 20,000 generations were disregarded as 'burn in'.

SYSTEMATIC PALAEONTOLOGY-GENUS AND SPECIES LEVEL TAXONOMY
As mentioned previously, the most historically important and commonly utilized teleosauroid genus Steneosaurus has been recognized as a 'wastebasket' taxon by researchers and has continuously been recovered as paraphyletic or polyphyletic in phylogenetic analyses (Mueller-Töwe, 2006;Wilberg, 2015b;Foffa et al., 2019;Johnson, Young & Brusatte, 2019). In addition, no type species had until recently been officially designated for Steneosaurus under International Commission on Zoological Nomenclature (ICZN) Code rules. Johnson, Young & Brusatte (2020) set out to rectify this problem by evaluating the validity of Steneosaurus. The authors designated Steneosaurus rostromajor Geoffroy Saint-Hilaire, 1825, as the type species of Steneosaurus, designated MNHN.RJN 134c-d as the lectotype, provided a thorough literature and descriptive review of the specimen, and compared it with other relevant teleosauroid taxa. Their final verdict considered S. rostromajor (MNHN.RJN 134c-d) to be a nomen dubium, and proposed that the genus Steneosaurus is undiagnostic, due to (1) lack of autapomorphic characters (2) poor preservation (3) a generic concept that has changed multiple times through time; and (4) uncertainty of teleosauroid ontogenetic variation and sexual dimorphism (Johnson, Young & Brusatte, 2020). Johnson, Young & Brusatte (2020) suggested that establishing a 'clean' foundation of teleosauroid taxonomy using diagnostic type species/specimens, with every nomenclatural act correctly formulated, was the next course of action. Therefore, we believe that it is necessary to erect new proposed teleosauroid genera first, as a direct result of the proposal of Steneosaurus as a nomen dubium. This article in Portable Document Format (PDF) signifies a published work in accordance with the ICZN. As such, the new genus and species names contained will be effectively published under ICZN Code from the electronic edition. This work and the nomenclatural acts contained within it have been registered in ZooBank, the online registration system for the ICZN. The following ZooBank LSIDs (Life Science Identifiers) and associated information may be viewed through a standard web browser by adding the LSID to the prefix http://zoobank.org/. The LSID for this publication is: urn:lsid:zoobank.org:pub:7CC3CA17-F08F-48AD-9F16-8537B6BAAC1F. CROCODYLOMORPHA Hay, 1930(sensu Nesbitt, 2011) THALATTOSUCHIA Fraas, 1901(sensu Young & Andrade, 2009) TELEOSAUROIDEA Geoffroy Saint-Hilaire, 1831 (sensu herein, see below) Plagiophthalmosuchus gen. nov.
Paratype-NHMUK PV OR 15500, a complete skull and mandible.
Scoring Sources-the holotype (NHMUK PV OR 14792), paratype and all referred specimens were studied first-hand. Photographs of DONMG were provided by D. Lomax.
Autapomorphic characters of Pla. gracilirostris-in the antorbital fenestra, the external fenestra is significantly larger than internal fenestra (over 25%); antorbital fenestra is moderately large, being at least half the diameter of the orbit; internal fenestra is approximately 50% of the length of the orbit; supratemporal fossa is slightly larger (~25%) than the length of the orbit; basioccipital sub-vertical and somewhat visible in occipital view; exoccipital-opisthotics are dorsoventrally slender and paraoccipital processes have a straight distal margin; orbit positioned laterally with a slight dorsal inclination; dorsal border at dentary-surangular is relatively straight; glenoid fossa of the articular oriented subtly anterodorsally.
Etymology-'Spoon lizard'. Mystrio refers to the spoon-shaped anterior rostrum in dorsal view, and saurus is the Latinized version of saûros (σayρoς), which is Ancient Greek for lizard. Diagnosis-same as the only known species (monotypic genus).
Scoring sources-NHMUK PV OR 14781 was studied first-hand. The holotype (HLMD V946-948) was examined using high quality photographs provided by S. Sachs, and also discussed at great length with S. Sachs.
Autapomorphic characters of Mys. laurillardi-well-developed and extensive ornamentation on the nasals; external nares oriented anteriorly; antorbital fenestra is sub-rectangular in shape; supratemporal fossae form an approximate isosceles trapezoidshape; medial margin of supratemporal arch relatively straight in dorsal view, with no significant concavity; prominent anterior notch in the dentaries; mandibular fenestra poorly elliptic; large robust teeth with numerous, conspicuous apicobasally aligned enamel ridges and a pointed apex, with more anteriorly-placed tooth crowns being procumbent.
Emended diagnosis-mesorostrine skull; well-developed and extensive ornamentation on the premaxillae, maxillae, frontal, prefrontal, lacrimal and postorbital; frontal ornamentation composed of small sub-circular to elongate pits that are closely spaced or, that can fuse and become a ridge-groove pattern (similar to Mycterosuchus); slight constriction of the snout anterior to the orbits (similar to Deslongchampsina); large and numerous neurovascular foramina on the premaxillae, maxillae and dentaries (shared with Machimosaurini); external nares 8-shaped in dorsal view (shared with the Chinese teleosauroid, I. potamosiamensis, Bathysuchus and Aeolodon); dorsoventrally deep premaxilla (similar to I. kalasinensis); anteroposterior premaxilla length less than 25% of total rostral length (shared with the Chinese teleosauroid, Mac. buffetauti and Mac. mosae); premaxilla anterior and anterolateral margins are orientated anteroventrally and extend ventrally in lateral view ( Diagnosis-same as the only known species (monotypic genus).
Scoring sources-the holotype (NHMUK PV OR 49126) was examined first-hand.
Autapomorphic characters of Cl. stephani-prefrontal is anteroposteriorly short and mediolaterally broadened; posterior projections of the nasals not elongated and level with prefrontal-orbit contact in dorsal view; anteromedial process of the frontal is posterior to the prefrontals; anteromedial process of the frontal is anteroposteriorly short and mediolaterally broad; jugal extends anteriorly to the prefrontal.
Etymology-'Wide crocodile'. Platys comes from the Greek platýs (πλaτύς) meaning wide (referring to the flattened, expanded osteoderms and dermal shield), and suchus is the Latinized form of the Greek soukhos (σοῦχος), meaning crocodile.
Scoring sources-the holotype (SMNS 9930) and MNHNL TU895 were examined firsthand. Additional information was taken from Westphal (1961Westphal ( , 1962. Autapomorphic characters of Pl. multiscrobiculatus-prefrontal and lacrimal both ornamented with meandering, elongated grooves; mid-and posterior squamosal well ornamented with small, circular, closely packed pits; frontal contribution to the intertemporal bar frontal wider than the parietal in dorsal view; jugal excluded from the orbit by lacrimal-postorbital contact; P1 and P2 do not form a couplet and are not oriented on the anterior margin of the premaxilla; tuberculum of the dorsal rib medium-sized; Figure 6 Platysuchus multiscrobiculatus. Platysuchus multiscrobiculatus (Berckhemer, 1929) Westphal, 1961 Nearly complete skeleton, with close-up views of (B) the skull, Age-Bathonian, Middle Jurassic.
Etymology-'(Long) Nose crocodile'. Myctero comes from the Latin mycto meaning nose, referring to the elongated rostrum of this taxon; suchus is the Latinized form of the Greek soukhos (σοῦχος), meaning crocodile.
Scoring sources-the holotype (NHMUK PV R 2167) and all referred material (excluding the NM skeleton) mentioned above were studied first-hand.
Autapomorphic characters of Myc. nasutus-overall cranium and mandible extremely rugose; elongate, slender rostrum (approximately 73% of total skull length); maxilla ornamented with an array of irregular patterns of deep rugosities and anastomosing grooves; reduced quadrate condyles; palatine anterior margin terminates level to 29th maxillary alveoli, or more distal alveoli; curvature of the angular is gradual in the anterior region, but more abrupt in the posterior-most region; on the retroarticular process, the length of the attachment surface for the adductor muscles is more than twice its width; D1 strongly anteriorly oriented; the neural arches of the posterior cervical vertebrae are taller than the vertebral centra; the posterior edge of the scapula is more strongly concave than the anterior edge; the humeral head is weakly posteriorly expanded and hooked with a club-like shape; the ulna is more than 25% longer than the radius; the pubic shaft is over 50% length of the pubic plate; anteromedial tuber of the femur is the largest of the proximal tubera; size of calcaneal tuber approximately 25% of total astragalus size; large, heavyset dorsal osteoderms with large, round-to-ellipsoid (D-shaped) irregular pits that are well separated from one another.
Emended diagnosis-longirostrine snout; tooth row and quadrate condyle unaligned and quadrate at a lower level, but both below the occipital condyle (shared with Indosinosuchus taxa); well-developed and extensive ornamentation on the premaxillae, maxillae, frontal, prefrontal, lacrimal and postorbital; frontal ornamentation composed of small sub-circular to elongate pits that are closely spaced or, that can fuse and become a ridge-groove pattern (similar to Mystriosaurus); rostrum narrows immediately anterior to the orbits (shared with I. potamosiamensis, Teleosaurus, Aeolodon, Bathysuchus, Sericodon and Seldsienean); premaxilla anterior and anterolateral margins are strongly anteroventrally deflected and extend ventrally ( Remarks-the skull and mandible of the NHMUK holotype was originally numbered PV R 2617, along with the associated postcranial material. The skull and mandible were then reregistered PV R 3577 in error (what year and by whom is unknown). Mycterosuchus has also been considered as a synonym of Steneosaurus leedsi (= Charitomenosuchus leedsi) in certain studies (Vignaud, 1995).
Diagnosis-same as the only known species (monotypic genus).
Autapomorphic characters of A. priscus-shallow elliptical pits on the frontal; length of the attachment surface for the m. pterygoideus posterior on the retroarticular process is short, and subequal to its width; neural spine and centrum heights of the mid-cervical vertebrae are approximately equal; distal coracoid with rounded edges and a deep coracoid foramen; extremely shortened ulna and radius relative to humerus; ulna with little curvature, only in the proximal-most region; metacarpals IV and V are similar in robusticity to II-III ; ischial plate sub-triangular; tibia 30-40% shorter than the femur; dorsal osteoderm ornamentation consists of large, well-spaced circular pits. Remarks-Crocodilus priscus (NHMUK PV R 1086) was the first teleosauroid genus to be scientifically named by von Sömmering in 1814. Von Meyer (1830) initially presented Aeolodon gen. nov., and prematurely used this genus for comparison with Rhacheosaurus (1831: 176) but did not provide a formal description until his 1832 volume. Comparing the specimen (NHMUK PV R 1086) to the modern gharial, Von Meyer (1832) noted the "heterodont" teeth (which was his basis for the new genus name) and the "limb bones and phalanges […] appear like in whales". It is also interesting to note that Geoffroy Saint-Hilaire (1831: 48) did not believe that Aeolodon ("le gavial de Sömmering": "Sömmering's gavial") could be referred to as either Teleosaurus or 'Steneosaurus' (mainly due to the fact that it was not found in the deposits near Caen, which Geoffroy Saint-Hilaire believed these two genera were restricted to). Despite coming from different localities, the holotype (NHMUK PV R 1086) and referred specimen (MNHN.F.CNJ 78) share the following combination of features: Holotype-NHMUK PV OR 43086, a partial rostrum.
Scoring sources-the holotype (NHMUK PV OR 43086) and the unnumbered LPP specimen were studied first-hand. D. Foffa provided high quality photographs of DORCM G.05067i-v, and B. megarhinus was also discussed at great length with D. Foffa.
Autapomorphic characters of B. megarhinus-shallow, minor ornamentation on the parietal (nearly imperceptible); extremely pronounced lateral expansion of the premaxilla with rounded, straightened lateral margins; the fifth dentary alveolar pair is posterolaterally oriented and on the posterior end of the mandibular spatula Emended diagnosis-longirostrine snout; rostrum narrows immediately anterior to the orbits (shared with I. potamosiamensis, Teleosaurus, Mycterosuchus, Sericodon, Aeolodon and Seldsienean); shallow, inconspicuous ornamentation of the premaxillae and maxillae (similar to the Chinese teleosauroid, Indosinosuchus, Sericodon and Aeolodon); no ornamentation on the prefrontal (shared with Plagiophthalmosuchus, I. potamosiamensis, Sericodon and Aeolodon); external nares are '8' shaped in dorsal view (shared with Mystriosaurus, the Chinese teleosauroid, I. potamosiamensis, Mycterosuchus and Aeolodon) and in anterior view (shared with Mystriosaurus, the Chinese teleosauroid, I. potamosiamensis and Aeolodon); external nares are anterodorsally oriented (shared with Plagiophthalmosuchus, the Chinese teleosauroid, Indosinosuchus, Platysuchus, Mycterosuchus, Aeolodon, Bathysuchus and Sericodon); reduced anteroposterior length of the external nares; more than 67% of total premaxilla length is posterior to the external nares (shared with Plagiophthalmosuchus, the Chinese teleosauroid, I. potamosiamensis, Mycterosuchus, Sericodon and Aeolodon); premaxillary anterior and posterior medial margin of external nares formed by two bulbous projections (shared with Mycterosuchus); the anterior and anterolateral margins of the premaxillae are strongly anteroventrally deflected and extend ventrally (shared with Mystriosaurus, the Chinese teleosauroid, Mycterosuchus and Platysuchus); inconspicuously ornamented maxillary dorsal surface (shared with the Chinese teleosauroid and Aeolodon), consisting of a shallow irregular pattern of ridges and anastomosing grooves; nasal, prefrontal, lacrimal are also ; the P1 and P2 alveoli are lateral to each other at the anterior margin of the premaxilla (shared with Mycterosuchus, Sericodon and possibly Aeolodon); the P3 and P4 are aligned on the lateral plane of the external margin more so than P2 (shared with Sericodon); the P1 and P2 are on the same transverse plane, and the lateral margin between the P2 and P3 is sub-rectangular (shared with Mycterosuchus, Sericodon and Aeolodon); anterior maxillary interalveolar spacing is sub-equal to longer than adjacent alveoli; lack of apical tooth carinae (shared with Sericodon); the pits on the dorsal osteoderms are circular and regularly organised in alternate rows (similar with Aeolodon); dorsal osteoderms reduced in size and thickness (shared with Aeolodon).
Remarks-Steneosaurus megarhinus was initially named and described by Hulke (1871) and was recently re-described within a new monotypic genus, Bathysuchus, by Foffa et al. (2019). Due to similar anatomical features of the cranium, stratigraphic horizons, and comparative measurements of the humerus and femur with Aeolodon, Foffa et al. (2019) concluded that these two genera were evidence of the first deep water, more pelagic teleosauroids.
Etymology-'Silk toothed', Serico comes from the Latin sēricus (Ancient Greek: Sêres [Σῆρες], possibly from Ancient Chinese ) meaning silk, and don from the Greek dónti (δόντι) meaning tooth. Refers to the slender, poorly ornamented dentition of this taxon.
Taxonomic note-Von Meyer (1845) initially diagnosed a series of teeth from the Kimmeridgian of Solothurn and Hannover as the type series of Sericodon; however, it is unknown if this material is still available, and Von Meyer did not designate a holotype. A lectotype can be proposed for one of the NMS (Switzerland) specimens, but this needs further clarification. The authors and colleagues plan a thorough description of this specimen, as well as additional Sericodon material, to allow for a formal designation of a lectotype. R2337, SMF R 431a-b, SMF R 4318, unnumbered Göttingen specimen) were examined first-hand.
Autapomorphic characters of Ser. jugleri-unornamented intertemporal bar; external nares weakly subcircular in dorsal view; palatal canals extremely shallow; lack of apical enamel ridges; tuberculum and articular facet of dorsal rib situated close to the lateromedial edge; posteromedial tuber of femur reduced.
Stratigraphic horizon-lower part of the Phu Kradung Formation, Khorat Group.
Scoring sources-the holotype (PRC-11) as well as PRC-238 were examined first-hand. Additional information was gleaned from Martin et al. (2019).
Autapomorphic characters of I. potamosiamensis-extremely anteroposteriorly elongated posterior nasal processes (reaching the medial margin of the orbit); substantially elongated anterior process of the nasal, near-parallel to the posterior margin of the antorbital fenestra; the D2-D3 interalveolar space is longer than that between the D1 and D2.
Stratigraphic horizon-lower part of the Phu Kradung Formation, Khorat Group.
Autapomorphic characters of I. kalasinensis-approximately 64% of total premaxilla length is posterior to the external nares; anteroposteriorly thickened postorbital bar.
Emended diagnosis-mesorostrine snout; tooth row and quadrate condyle unaligned with quadrate at a lower level, and both below the occipital condyle ( 2. Premaxillary and maxillary neurovascular foramina are nearly 2x larger in PRC-239 than PRC-11, notably in the premaxillae; 3. External nares 'B'-shaped in anterior view in PRC-239, whereas in PRC-11 they are somewhat'8-shaped'; 4. Premaxillary length posterior to the external nares is between 50-65% in PRC-239, whereas in PRC-11 the premaxilla length posterior to the external nares is over 67%; 5. Minimum width of the frontal is subequal to orbital width in PRC-239, whereas in PRC-11 the frontal width is noticeably narrower than the orbital width; 6. Dorsal margin of the orbit flush with the skull dorsal surface in PRC-239 (although this may be due to dorsoventral crushing) whereas in PRC-11 the dorsal margins of the orbits are prominently upturned; and 7. Poorly elliptic external mandibular fenestra in PRC-239, whereas in I. potamosiamensis the mandibular fenestra is highly elliptic (anteroposteriorly elongated).
In addition, I. kalasinensis is never recovered as sister taxon to I. potamosiamensis in the phylogenetic analyses conducted below, and I. kalasinensis lacks all autapomorphies seen in I. potamosiamensis.
Etymology-'Large vertebra.' Macro is from the Greek makrýs (mάκρος) meaning long, and spondylus is from the Ancient Greek spóndylos (σπόνδyλος) meaning vertebra. Refers to the long, amphicoelous vertebrae.
Scoring sources-the holotype (MMG BwJ 595), as well as a multitude of specimens from Germany, England and Luxembourg, were studied first-hand. Autapomorphic characters of Ma. bollensis-the proximal region of the humerus is strongly proximodistally elongated and weakly posteriorly hooked; ulna with a well-developed distal curvature.
Designation of neotype-herein we formally designate MMT P28-1 as the neotype of Se. megistorhynchus. In order to be in full accordance of Article 75 of the ICZN Code, specifically Article 75.3, we make the following statements: 1. This designation is made with the objective of clarifying the taxonomic status of Se. megistorhynchus.
2. Our assertion of the characters that we regard as distinguishing Se. megistorhynchus from other teleosauroid taxa is listed in the species diagnosis below.
3. The neotype can be recognized through both the following diagnosis and Fig. 15.
4. The holotype is presumed destroyed in 1944 during the bombing of Caen.
5. The holotype, in addition to a partial skull, included a complete mandible; E. Eudes-Deslongchamps (1867: 217) stated that the holotype of Se. megistorhynchus consisted of a "Museau très-allonge', grêle, étroit et aplati dans toute sa longueur" ("Very elongated muzzle, slender, narrow and flattened along its entire length"). As such, the neotype is consistent with what is known of the former name-bearing type.
6. Unfortunately, the locality of the neotype is not known. However, it and the holotype are from the same age (Bathonian) and country (France), and have been referred to as the same species.
7. Se. megistorhynchus is a slender, longirostrine form, which differs from the genera Deslongchampsina (mesorostrine) and Yvridiosuchus (durophagous), which are found in the same stratigraphic horizon and location. In addition, the neotype displays has several distinct features that differ from Deslongchampsina and Yvridiosuchus (e.g. telescopic orbits).
8. The neotype is the property of an internationally recognized scientific institution at the Musée d'art et d'histoire de Toul (MMT), which maintains a research collection with suitable facilities for preserving name-bearing types and is accessible for study.
Autapomorphic characters of Se. megistorhynchus-small, circular, noticeably spaced ornamentation on prefrontal and lacrimal; extremely interdigitated anterior margin of the palatines; relatively deep, subcircular neurovascular foramina in the posterior region of the dentary, seen in lateral view; deep coronoid groove; dorsal osteoderms with large, irregularly shaped and elongated pits with raised areas in between pits, and a small yet well-developed keel situated in the middle of the osteoderm.
Emended diagnosis-longirostrine skull; rostrum narrows immediately anterior to the orbits ( Remarks-despite fragmentary material, we consider Seldsienean as a distinct taxon because it is the only longirostrine form present in the Great Oolite Group (UK) during the Bathonian.

Locality-Peterborough, UK.
Stratigraphic horizon-Peterborough Member, Oxford Clay Formation, Ancholme Group. Scoring Sources-the holotype (NHMUK PV R 3320) as well as all referred specimens mentioned above were examined first-hand.

Remarks-Both
Diagnosis-same as the only known species (monotypic genus). Holotype-A partial skull associated with a partial symphyseal section of the mandible, pelvis, hindlimb, two vertebrae and dorsal osteoderms. Destroyed in 1944.
Autapomorphic characters of D. larteti-feeble constriction of the premaxillae posterior to the external nares, giving the premaxillae a more rounded, 'globular' appearance in dorsal and ventral views; posterior processes of the nasals are mediolaterally thin; gradual and well-developed anteroventral sloping of the nasals.  Proexochokefalos and Neosteneosaurus); frontal width subequal with orbital width (shared with the Chinese teleosauroid, Mycterosuchus, Proexochokefalos, Yvridiosuchus, Mac. hugii and Mac. rex); small basioccipital tuberosities (similar to Bathysuchus); palatine anterior margin terminates distal to the 20th maxillary alveoli (shared with Charitomenosuchus, Mycterosuchus and Bathysuchus); mandibular symphysis slightly less than half the mandibular length, between 45 and 50% (shared with Mystriosaurus, I. potamosiamensis and Proexochokefalos); deep, well-developed reception pits throughout the anterior-to mid-maxilla and gradually disappear (similar to Mystriosaurus, Charitomenosuchus and Proexochokefalos); teeth are robust, slightly curved and weaklycompressed, with pointed apices and high relief enamel ridges (similar to Neosteneosaurus).
Autapomorphic characters of Pr. heberti-premaxillae dorsoventrally high in lateral view (approximately 38 mm dorsoventral length, from dorsal-most area to tooth row); occipital tuberosities large and well-developed; slightly mediolaterally compressed teeth with pointed apices throughout the dentary series; faint enamel ridges on apical third of teeth; 79-80 posterior curvature of the teeth throughout the entire dental series.
Emended diagnosis-mesorostrine skull; tooth row and occipital condyle aligned, and quadrate condyle at a lower level ( Proexochokefalos cf. bouchardi (Sauvage, 1872) comb. nov. (Fig. 19) Holotype-A partial specimen initially composed of a skull, mandible and assorted vertebrae (Vignaud, 1995). Currently missing and/or destroyed. (1872) Remarks-the mandible of the holotype disappeared, while remnants of the skull material were initially sent to BHN2 (and was considered the lectotype (presumably BHN2 R 59)). However, this museum was closed in 2003 and the current whereabouts of the material is unknown. In addition, Vignaud (1995) considered the remaining vertebrae of the holotype (location also unknown) as the paralectotype, with no formal explanation as to why. In 1892, M. Makinsky discovered the skull figured in Lepage et al. (2008) in the Pictonia baylei ammonite zone (lower Kimmeridgian) near Villerville (Calvados, France). Buffetaut & Makinsky (1984) described it as 'Steneosaurus' cf. bouchardi; currently the location of this skull, as with all holotype material, is not known (Y. Lepage, 2018, personal communication). Due to the close phylogenetic placement of this taxon to Proexochokefalos heberti, it is currently considered to be in the same genus.
Description-maxillae ornamented with numerous, weakly-to strongly developed grooves; moderately interdigitating premaxilla-maxilla dorsal suture (shared with Mystriosaurus, Proexochokefalos, Andrianavoay, Neosteneosaurus and Machimosaurini); deep, pronounced reception pits throughout the entirety of the maxilla (shared with Andrianavoay, Neosteneosaurus, and Machimosaurini); at least 27 maxillary alveoli; mainly circular, well-spaced maxillary alveoli throughout the entirety of the rostrum; posterior maxillary alveoli slightly smaller than anterior maxillary alveoli (similar to Yvridiosuchus); well-developed, pronounced enamel ridges near the base of the tooth. . Currently, only one taxon can hypothetically be referable to S. rostromajor, Neosteneosaurus; however, due to lack of autapomorphic features, uncertainty of teleosauroid ontogenetic and sexual dimorphic stages, a generic concept that has changed multiple times, and poor preservation, S. rostromajor is currently regarded as a nomen dubium (Johnson, Young & Brusatte, 2020).
Scoring sources-the holotype (NHMUK PV R 1999) was examined first-hand.
Autapomorphic characters of A. baroni-sparse, small, deep subcircular foramina on the posterior and lateral margins of the external nares; anteroposteriorly thin posterior-most parietal.
Diagnosis-same as the only known species (monotypic genus).
Scoring sources-the holotype (MNHN.RJN 118), as well as all additional referred specimens, were examined first-hand.
Autapomorphic characters of N. edwardsi-posterior (distal) teeth with sub-pointed apices (are not blunt and rounded but significantly less pointed than in anterior [mesial] and middle teeth); tuberculum and articular facet of the dorsal rib positioned on the lateromedial edge.
Scoring sources-the neotype (OUMNH J.1401), as well as all referred specimens mentioned above, were studied first-hand.
Autapomorphic characters of Y. boutilieri-heavily ornamented lacrimal, appearing perforated in lateral view; extreme elongation of the anterior jugal, so that it participates in the posterior margin of the antorbital fenestra; orbit subcircular in shape; anterior process of palatine U-shaped; width of retroarticular process is narrower than the glenoid fossa. See Johnson, Young & Brusatte (2019) for more detail.
Scoring sources-the holotype (NHMUK PV R 3168) and all referred specimens mentioned above were studied first-hand.
Autapomorphic characters of L. obtusidens-the rostrum external surface is strongly convex, in particular the nasals; partial or complete fusion of the internasal suture; nasal midline cavity poorly developed; eight cervical vertebrae; dorsoventrally curved cervical ribs; anterior process of ilium is anteroposteriorly shortened; acetabulum is shallow and poorly developed; shallow supraacetabular crest on the ilium; anterior ischial process reduced; dorsal osteoderms with small-to-large, irregularly shaped pits that radiate from the centre of the keel and are arranged in a starburst pattern (to a certain extent similar to Mac. mosae Etymology-'Pugnacious lizard'. Machimo is derived from the Greek machimoi (mάχιmoι), meaning pugnacious (having a combative nature, presumably referring to the robust dentition), and saurus is the Latinized version of sauros (σayρoς), which is Ancient Greek for lizard.
Geographical range-Africa (Ethiopia and Tunisia) and Europe (England, France, Germany, Portugal, Spain and Switzerland).
Generic diagnosis-rostrum wider than high; three alveoli per premaxilla; first premaxillary alveoli strongly oriented anteroventrally; 18-22 alveoli per maxilla; 19-25 alveoli per dentary; maximum supratemporal length is greater than 27% relative to maximum basicranial length; extreme elongation of the supratemporal fenestrae, with the anteroposterior length twice the mediolateral length; medial quadrate hemicondyle considerably smaller than the lateral quadrate hemicondyle; presence of carinae on teeth variable; tall axis neural spine terminating on a plane dorsal to the pre-and postzygapophyses in lateral view; axis neural spine posteriorly expanded in lateral view. Holotype-SMNS 91415, a complete skull and mandible (as well as in situ teeth) with associated partial postcranial skeleton including cervical and dorsal vertebrae, one coracoid and multiple osteoderms.
Scoring sources-the holotype (SMNS 91415) was examined first-hand, and additional information was gleaned from Young et al. ( , 2015b.
Autapomorphic characters of Mac. buffetauti-anterolateral frontal projections between nasals and prefrontals; squamosal approximately level with occipital condyle; retroarticular process is slightly longer than wide; low post-symphyseal tooth count of the dentary; dorsal margin of the axis neural arch is strongly concave in lateral view; tuberculum and articular facet of dorsal ribs slightly situated on the medial edge; elongated coracoid glenoid process that extends considerably from the proximal coracoid, and sub-isosceles triangle-shaped in lateral view; anterior margin of the coracoid postglenoid process is slightly concave and terminates approximately in the same frontal plane as the glenoid; posterior margin of the coracoid postglenoid process is strongly concave and terminates approximately in the same frontal plane as the posterior end of the glenoid process; dorsal osteoderms with generally small, irregularly shaped pits arranged in a random pattern, with a shallow keel.
Emended diagnosis-brevirostrine skull; rostrum wider than high; two parallel lines of large, circular neurovascular foramina on the premaxillae and maxillae, and a clustering of foramina on the lateral surface of the premaxillae ( ; posteroventral margin of ischial plate is sub-square (shared with Lemmysuchus); tibial tuberosity angled ventrally (shared with Lemmysuchus); dorsal osteoderms ornamented with small-to-large, irregularly shaped pits that radiate from the centre of the keel and are arranged in a starburst pattern (similar to an extent in Lemmysuchus).
Remarks-the diagnosis of Machimosaurus mosae has until recently been uncertain. Sauvage & Liénard (1879) initially diagnosed this taxon based on an incomplete skull, mandible and postcranial material. However, Krebs (1967) viewed it as a junior synonym of Machimosaurus hugii. Hua (1999) then regarded it as a distinct taxon and proposed a new diagnosis for it, based on a new specimen from the Kimmeridgian of Boulonnais (northwestern France) containing the skull, mandible and partial postcranial material. Pierce, Angielczyk & Rayfield (2009) also considered Mac. mosae to be distinct from Mac. hugii, due to the position of it within their geometric morphometric analysis. However, Martin & Vincent (2013: 194) criticized Hua (1999) and Pierce, Angielczyk & Rayfield (2009)'s diagnoses, writing 'most of the content of these diagnoses reveal to be either diagnostic at the genus level or to characterize all Teleosauridae'. Martin & Vincent (2013: 195) then showed that high variation in maxillary and dentary tooth counts among the various Callovian teleosaurids is 'sufficient difference to discard such an interpretation (the synonymy)'. Martin & Vincent (2013) synonymized Mac. mosae with Mac. hugii, thus re-opening an old debate as to whether Machimosaurus represented a monotypic genus, or if the differences found between Mac. mosae and Mac. hugii were ontogenetic. However, other subsequent studies by Vignaud (1995), Hua (1999)  There are also certain postcranial features that differentiate Mac. mosae and Mac. hugii, including the shape and size of the coracoid postglenoid and glenoid processes .
Autapomorphic characters of Mac. hugii-external surfaces of the cranial bones are poorly ornamented, particularly the rostrum and near the orbits; paraoccipital processes greatly enlarged, mediolaterally elongated and with expanded lateral ends, and are larger than the exoccipital-opisthotics; in occipital view, the inter-basioccipital tubera notch is a large inverse 'U'-shape; dentary interalveolar spacing uniformly narrow.  Fanti et al. (2016) described this specimen as being Hauterivian in age, the exact age is unclear, due to uncertainty of the geological age of the area, as well as previously disregarded biostratigraphic invertebrate fauna (Dridi & Johnson, 2019;Dridi, 2020). It is also important to note that Mac. rex does not display any autapomorphic characters, given its extremely poor preservation.

CHARACTER DESCRIPTIONS
New characters pertaining to teleosauroids The 38 new characters introduced here were formulated to describe thalattosuchian, specifically teleosauroid, anatomical variation. These characters are relevant to the interrelationships of teleosauroids, and many highlight previously unexamined morphological divergence between two large subclades within the group (see below). These characters are new and are here used in a cladistic analysis for the first time, and all states (indicated by a number in brackets) are subsequently figured. Character numbering follows the numbering used in the full list of characters for the present analysis (see Supplemental Data SD1). More detailed descriptions and comparisons of all following characters have been provided in the Supplemental Data SD4.
This character was inspired by the variety of ornamentation patterns found on the prefrontal of teleosauroid taxa. Ornamentation is either absent (state 1) or comes in the form of shallow to deep pits or shallow to deep, elongated and thin grooves (state 0). State 1 occurs in very few teleosauroids, including the basal teleosauroid 13. Ornamentation on lacrimal in dorsal view: present (0), with shallow to deep pits and/or grooves, or absent (1) (Fig. 29).
As with the above character, the ornamentation displayed on the lacrimal (=lachrymal) differs between taxa. Ornamentation is either absent (state 1) or comes in the form of shallow to deep pits, as well as shallow to deep, elongated and thin grooves (state 0). The majority of teleosauroids (Mystriosaurus: NHMUK PV OR 14781; Platysuchus: SMNS Charitomenosuchus (NHMUK PV R 3320) and Sericodon (Schaefer, Püntener & Billon-Bruyat, 2018). As discussed in ch. 12, lack of ornamentation has previously been attributed to juveniles (Vignaud, 1995); however, this character was scored using adult specimens.
The frontal of teleosauroids is a single bone that is consistently ornamented throughout the majority of the group, excluding Bathysuchus (unnumbered LPP specimen) and juveniles (e.g. SMNS 10,000). Ornamentation either extends from the centre of the frontal to the anterior-and lateral-most areas (state 0) or is restricted to the midline or centre of the frontal (state 1), with minimal extension.
Plagiophthalmosuchus ( It has been suggested that Bathysuchus lacks any frontal ornamentation (Vignaud, 1995), similar to juvenile individuals. However, there may possibly be weak, nearly unnoticeable pits and grooves restricted to the midline of the frontal in this taxon (Fig.), in an LPP unnumbered specimen (Foffa et al., 2019). Due to this uncertainty, this taxon was scored as (?).
This character focuses on the total anteroposterior premaxillary length in relation to the total anteroposterior rostrum length of a cranium. When defining the rostral length, this refers to the length between the anterior-most premaxillae to the anterior orbital margin.

Premaxilla in dorsal view
, the anterior and posterior medial margins of the external nares are formed by two bulbous projections, which are either absent (0) or present (1) (Fig. 31).
In most teleosauroids, the medial margins of the external nares are minimally convex (state 0), causing the external nares to appear D-shaped in dorsal view. This is the condition seen in the basal Plagiophthalmosuchus (NHMUK PV OR 14792) in addition to Mystriosaurus (NHMUK PV R OR 14781), Indosinosuchus (PRC11; PRC-239), the  In certain taxa, however, both the anterior and posterior margins are strongly convex, and appear 'bulging' in dorsal view. This condition (state 1) is synapomorphic in a unique clade containing Mycterosuchus (NHMUK PV R 2617), Bathysuchus (unnumbered LPP specimen) (Foffa et al., 2019), and possibly Aeolodon (MNHN.F.CNJ 78) (however, specimens of this taxon are dorsoventrally crushed and slightly distorted, so it is difficult to say with certainty if it is present).
In the majority of teleosauroids (e.g. the Chinese teleosauroid: IVPP V 10098; Platysuchus: SMNS 9930; Mycterosuchus: NHMUK PV R 2617; Lemmysuchus: LPP.M.21), including the basal-most teleosauroid (Plagiophthalmosuchus: NHMUK PV OR 14792), the posterior processes of the nasals reach or extend slightly past the anterior rim of the orbits (state 0). In addition, these processes are positioned medially, slightly mediolaterally thin in the posterior-most area, and do not come into close contact with the medial orbital margin. However, I. potamosiamensis (PRC-11) clearly possesses state 1, in which the nasals have extraordinarily anteroposteriorly elongated posterior processes; these are mediolaterally thin and contacts the medial rim of the orbit (see Martin et al., 2019).
124. Frontal, anteromedial process shape and length relative to nasals: anterior projection of frontal is mediolaterally broad and does not extend far anteriorly past anterior orbital rim into nasals (0) or anterior projection of frontal is mediolaterally thin and extends anteriorly past anterior orbital rim into nasals (1) (Fig. 32).
In the majority of teleosauroids, this process is triangular, thin and anteromedially elongated, usually extending past the anterior orbital margin (state 1). This is seen in taxa such as the basal-most form Plagiophthalmosuchus (NHMUK PV OR 14792) as well as It is interesting to note that the anteromedial frontal processes in Yvridiosuchus, Indosinosuchus, Charitomenosuchus and Mac. buffetauti are considerably more elongated and mediolaterally thin than in the other aforementioned taxa.
Most teleosauroids do not have these extra frontal projections; instead, the frontal suture is flush with that of the posterior nasal processes (state 0). This condition is clearly seen in the basal teleosauroid Plagiophthalmosuchus (NHMUK PV OR 14792) and the Chinese teleosauroid (IVPP V 10098), Indosinosuchus (PRC-11, PRC-239), Platysuchus The presence of these frontal projections is an apomorphic state, however, in the taxon Mac. buffetauti (Martin & Vincent, 2013;SMNS 91415), in which they are large, mediolaterally broadened and clearly noticeable (state 1).
The majority of teleosauroids have a shortened anterior process of the jugal that does not extend past the anterior orbital margin (state 0). This is clearly seen in the basal form 184. Maxilla in palatal view, shape of anterior maxilla is tapering (subtriangular) (0) or straightened (sub-rectangular) (1) (Fig. 34).
This character focuses on the anterior premaxilla-maxilla contact in palatal view, which is positioned parallel to the fourth premaxillary alveolus. State 1 is a synapomorphic character for members of Teleosauroidea (e.g. the Chinese teleosauroid: IVPP V 10098; Yvridiosuchus: OUMNH J.1401); the contact is horizontal and straight, and sub-rectangular in shape. This character is one key difference from Metriorhynchoidea, in which the contact is subtriangular and anteriorly directed (state 0) (e.g. Metriorhynchus superciliosus: LPP.M.48). 208. Paraoccipital process approximately the same size (0) or substantially larger than the remainder of the exoccipital-opisthotic (1) (Fig. 35).

Angular dorsal curvature is gradual (0) or sharp and abrupt
In most teleosauroids, the ventral margin of the angular gradually curves posterodorsally (state 0). This condition is seen in Indosinosuchus  291. Maxilla, reception pits are either absent, shallow throughout, or conspicuous only in the anterior maxilla (0) or pronounced and deep throughout the entirety of the maxilla (1) (Fig. 38).
State 0 includes taxa that have either shallow or absent reception pits on the maxillae; however, it is important to note that reception pits are present in all teleosauroids, so for the purposes of this analysis, state 0 of character 291 focuses purely on taxa with shallow reception pits. These may vary substantially in terms of noticeability; for example, In some taxa, the reception pits are deep and noticeable throughout the near-entirety or entirety of the maxilla, notably so in the anterior and middle regions, although they do become smaller when progressing posteriorly (state 1). This condition is seen in machimosaurins (e.g. Lemmysuchus: NHMUK PV R 3618) as well as Andrianavoay (NHMUK PV R 1999), S. rostromajor (MNHN.RJN 134c-d, to some extent) and large individuals of Neosteneosaurus (PETMG R178).
The first (P1) and second (P2) premaxillary alveoli are situated anterior to the third (P3) and fourth (P4), which are positioned posterolaterally. The fifth (P5) premaxillary alveolus (present in Bathysuchus, Sericodon and Platysuchus) is positioned dorsally in comparison to the P1 to P4 (Foffa et al., 2019). As such, the interalveolar distance varies between these alveoli. The P1 and P2 can be well separated in a way similar to that between the P3 and P4; the interalveolar spacing is large and noticeable, with the adjacent alveoli at a further distance from one another. This condition (state 0) occurs in  In contrast, in the majority of teleosauroids the P3 and P4 remain separate, but the P1 and P2 are situated closely together and are either separated by a small, thin interalveolar lamina, or appear slightly merged together, thereby creating a P1-P2 'couplet' (state 1). This state is seen in Mystriosaurus (NHMUK PV OR 14781), the Chinese teleosauroid (IVPP V 10098), I. potamosiamensis (PRC-11) and one subclade of teleosauroids (e.g. Macrospondylus SMNS 18672; Charitomenosuchus: NHMUK PV R 3806; Proexochokefalos: MNHN.F 1890-13; Lemmysuchus: NOTNH FS3361). Note that this character is not applicable for taxa that have fewer than four premaxillary alveoli (Machimosaurus).
In most teleosauroids, the interalveolar spacing is generally noticeable and well-developed between the P3 and the P4, but it is usually small (possibly due to both alveoli being quite large); the alveoli are therefore closely spaced together, forming a couplet (state 0). This is present in most teleosauroids (e.g. G.05067i) and the Chinese teleosauroid (IVPP V 10098), in which the P3-P4 are widely spaced apart from one another, and therefore do not form a couplet. Note that this character is not applicable for taxa that have fewer than four premaxillary alveoli (Machimosaurus).
295. Premaxilla, both P1 and P2 do not form a couplet and are either not oriented on the anterior margin of the premaxilla (0) or are oriented on the anterior margin of the premaxilla (1) (Fig. 39).
In certain teleosauroids, if the P1-P2 alveolar complex does not form a couplet, these two alveoli are positioned either on or slightly ventral to the anterior margin of the premaxilla. In Platysuchus (SMNS 9930), the P1 and P2 do not form such a couplet and both alveoli are not oriented on the anterior margin of the premaxilla (state 0). However, in the genera Bathysuchus (DORCM G.05067i, unnumbered LPP specimen), Sericodon (SCR011-406 in Schaefer, Püntener & Billon-Bruyat, 2018) and Mycterosuchus (CAMSM J.1420), the P1 and P2 do not form a couplet but are noticeably oriented on the anterior margin of the premaxilla (state 1). Note that this character is not applicable for taxa that have fewer than four premaxillary alveoli (Machimosaurus).

296.
Premaxilla with no strong lateral expansion (0) or strong lateral expansion so that P3 and P4 are aligned on the lateral plane of the external margin, more so than P2 (1) (Fig. 39).

297.
Premaxilla, very small first premaxillary alveolus with the second premaxillary alveolus being much larger (0) or the first and second premaxillary alveoli are relatively the same size (1) (Fig. 39).
In most teleosauroids, the size of the P1 and P2 are relatively the same, with both being slightly smaller than the P3 and P4 (which is often the largest, as it houses the large fourth premaxillary tooth) (state 1). This condition is observed in I. potamosiamensis In certain teleosauroids, the P1 is considerably smaller than the P2, with the P1 being 25% or less the size of the P2 (state 0). This condition is observed in the Chinese teleosauroid (IVPP V 10098) and Macrospondylus (SMNS 81699).
In teleosauroids, the enamel ridges are either faint and/or difficult to see (e.g. Plagiophthalmosuchus: MNHNL TU515), or noticeable and well-developed (e.g. Mycterosuchus: NHMUK PV R 2617). Enamel ridges are present on the entirety of the crown, including the apex (state 1) in the basal-most form Plagiophthalmosuchus
Most teleosauroids that can be scored for this character exhibit T-shaped (in dorsal view) cervical ribs where the anteroposterior ridge is horizontal or straightened (state 0) (Platysuchus : SMNS 9930); Mycterosuchus: NHMUK PV R 2617; Charitomenosuchus: NHMUK PV R 3806. However, in Lemmysuchus (NHMUK PV R 3168), the largest, most posteriorly placed cervical ribs have a distinct dorsomedial curvature along the anteroposterior ridge, appearing slightly concave in lateral view (state 1).

398.
Second sacral vertebrae, the anterior margin of the posterior area of the second sacral vertebra has either a small, non-expanding flange (0) or a large, expanded and projecting flange (1) (Fig. 43).
In crocodylomorphs, the posterior area of the second sacral vertebra has an anterior margin that is both anteroposteriorly and dorsoventrally expanded into a projection or 'flange' of bone, which allows for a secure attachment to the ilium, thus influencing body movement. This 'flange' is either small and non-expanding (state 0), or noticeably expanded and anteroposteriorly protruding (state 1). All scored teleosauroids exhibit state 1, as there is always an expanded flange present on the anterior margin; however, the size and development differ. In the taxa Mycterosuchus (NHMUK PV R 2617), Charitomenosuchus (NHMUK PV R 3806), Lemmysuchus (NHMUK PV R 3168) and Mac. mosae (Hua, 1999;, the flange is considerably larger, more pronounced and well-developed. In Macrospondylus (MMG BwJ 595) and Neosteneosaurus (NHMUK PV R 3701) the flange is still present, but it is much smaller and less obvious.
In certain teleosauroids, the longitudinal ridge (or keel) on the dorsal osteoderms is anteroposteriorly elongated but shallow (state 0). This condition is seen in  In more derived teleosauroids, the keel of the sacral osteoderms is elongated, well-developed and thickened (state 1). State 1 is well exemplified in large specimens of Neosteneosaurus (PETMG R178) as well as the machimosaurin Lemmysuchus (NHMUK PV R 3168).

Previous characters pertaining to teleosauroids
In addition to the 38 new characters described above, several original characters from the 2016 H+Y dataset are key in differentiating between various teleosauroid taxa. In particular, 19 characters are anatomically distinct, variant and important in teleosauroids and are described in detail as follows (as mentioned previously, all following characters are thoroughly described in SD4): 10. Rostrum narrows markedly in dorsal view immediately in front of the orbits (0), or there is no narrowing (1) (Fig. 52).
On the lateral premaxillae and maxillae, teleosauroids possess numerous neurovascular foramina. These openings are possibly involved with multiple mechanoreceptory function such as prey detection, tactile discrimination or disruption in the surrounding water (Soares, 2002;Leitch & Catania, 2012). In most teleosauroids, the neurovascular foramina are small and subcircular in shape on both the premaxilla and maxilla, and are generally consistent in size and number. On the premaxilla, these foramina are restricted to the anteroventral and lateroventral margins of the external nares. On the ventrolateral surface of the maxilla, dorsal to the tooth row, they form a single line and are relatively well spaced. This condition (state 0) is seen in taxa such as the basal-most teleosauroid Plagiophthalmosuchus (NHMUK PV OR 14792) and Platysuchus (SMNS 9930), Mycterosuchus (NHMUK PV R 2617), Macrospondylus (PMU R161), and Neosteneosaurus (NHMUK PV 2865). Deslongchampsina (OUMNH J. 29851) also has restricted foramina on the premaxilla as well as a single line on the maxilla; however, the foramina are larger than those seen in other taxa with state 0, and are slightly anteroposteriorly elongated on the maxilla (most notably at the anterior and middle areas of the rostrum  : these taxa display large, deep, numerous, sub-circular neurovascular foramina (although the foramina in Mystriosaurus are smaller than in machimosaurins). The premaxillary openings are generally circular in shape, located around the ventral, lateral and anteroventral margins of the external nares and cluster together (especially around the external nares' lateral margins). On the maxilla, the foramina are more anteroposteriorly elongated and situated in two parallel lines, one dorsal to the tooth row with an additional line above it (state 1). The foramina are closely spaced together at the anterior part of the maxilla, but they gradually become more distanced from one another further posteriorly. In addition, it is interesting to note that the premaxillary foramina are 34. External nares oriented anteriorly or anterodorsally (0), or dorsally (1) (Fig. 54).
In a certain group of predominately Laurasian teleosauroids, the external nares face either anteriorly or anterodorsally (state 0). This condition occurs in Mystriosaurus  48. Premaxilla in lateral view, the anterior and anterolateral premaxillary margins are not sub-vertical, or do not extend ventrally (0), or the anterior and anterolateral margins are orientated anteroventrally and extend ventrally (1) (Fig. 53).
In one teleosauroid subclade, the anterior and anterolateral margins of the premaxilla are not sub-vertical and do not extend ventrally (state 0) when compared to the rest of the premaxilla; rather, they are anterodorsally curved in a continuous arc throughout. This condition is seen in the basal teleosauroid Plagiophthalmosuchus ( 83. Antorbital fenestrae/cavity, absent (0) or present (1) (Fig. 52).
In most teleosauroids, a small, slit-like or subcircular antorbital fenestra is present (state 1). This condition is seen in taxa such as Mycterosuchus (NHMUK PV R 2617), Indosinosuchus
Teleosauroids show variance in the shape of the supratemporal fenestrae. Most taxa have a sub-rectangular shaped fenestra, in which the anteroposterior axis is greater than 10% longer than the lateromedial axis (state 0). This is the condition seen in Mac. mosae: IRSNB cast, Mac. hugii: NMS 7029) the supratemporal fenestrae are extremely elongated and parallelogram-shaped (state 5), with the lateral and medial margins, and anterior and posterior margins being sub-parallel. This state is a putative apomorphy within machimosaurins.
In most teleosauroids, the anterior margin of the supratemporal fenestra is not anterolaterally expanded, and the anterolateral corners of the supratemporal fossae are parallel to the anteromedial corners, which makes the anterior margin of the supratemporal fenestrae appear horizontal in dorsal view (state 0). This condition is seen in the basal teleosauroid Plagiophthalmosuchus (NHMUK PV OR 17892) as well as one teleosauroid subclade (e.g Macrospondylus MMG BwJ 565; Charitomenosuchus: NHMUK PV R 3320; Proexochokefalos: MNHN.F 1890-13; Lemmysuchus: NHMUK PV R 3168; Mac. buffetauti: SMNS 91415). However, in the second subclade, the anterolateral corners of the supratemporal fossae are noticeably more inclined anteriorly than the anteromedial corners of the supratemporal fossae (state 1), giving the anterior margin an anteroposteriorly tilted appearance in dorsal view. State 1 is seen in Mystriosaurus 104. Supratemporal fenestrae, overall anteroposterior length is either less than or sub-equal to the anterior width (0), or is twice as long as the anterior width, or more (1) (Fig. 55).
This character is related in part to ch. 102, specifically regarding the parallelogramshaped supratemporal fenestrae see in Machimosaurini. In most teleosauroids, the anteroposterior length of the supratemporal fenestrae is approximately the same as the width (state 0). This condition is in the basal-most form Plagiophthalmosuchus In more derived teleosauroids, the anteroposterior width of the supratemporal fenestrae are approximately twice as long as the width (state 1). This condition is in Proexochokefalos (MNHN.F 189013), Pr. cf. bouchardi (Lepage et al., 2008), Neosteneosaurus (PETMG R178) and machimosaurins (e.g. Lemmysuchus: NHMUK PV R 3168).

151.
The circumorbital dorsal margins of the orbits are flush with the skull dorsal surface (0), upturned (prominent along the orbital medial margin in dorsal view, with the frontal interorbital margins being upturned) (1), or upturned along with the posterior margins (the frontal lateral process anterior margins are also upturned) (2) (Fig. 52).
In the majority of teleosauroids, the orbital dorsal margins are flush (=flattened) with the skull dorsal surface (state 0) and display no evidence of any dorsal upturn. This condition is seen in the basal teleosauroid Plagiophthalmosuchus 158. Orbit, the postorbital is excluded from the orbit posteroventral margin or only present in the posteroventral margin (0), or the postorbital reaches the orbit posteroventral margin and extensively forms part of the orbit ventral margin (1) (Fig. 56).
In certain teleosauroids, when examining the anterior exposure of the basisphenoid in palatal view, this bone is either absent or terminates approximately at the level of the anterior-most quadrates (state 0). This is the condition seen in the Chinese teleosauroid (IVPP V 10098), I. potamosiamensis (PRC-11), Teleosaurus (MNHN AC 8746) and Mycterosuchus (CAMSM J.1420). In the majority of teleosauroids, the basisphenoid is well exposed along the palatal surface anterior to the quadrates and bifurcates the pterygoids (state 1), which is caused by the posterior expansion of the posterior margin of the pterygoid. State 1 is a putative synapomorphy of one teleosauroid subclade and is seen in 327. Teeth along the entirety of the tooth row, with sharp, pointed apices (0) or blunt, round apices (1) (Fig. 40).
Teeth that are elongate and slender with pointed apices (state 0) can clearly be seen in the basal-most form Plagiophthalmosuchus (MNHNL TU515) and in most teleosauroids Neosteneosaurus (PETMG R178) possess teeth with pointed apices (and are therefore scored as state 0), it is important to note that the overall dentition of these four genera are more robust than in the other aforementioned teleosauroids. In particular, the posterior teeth of Neosteneosaurus (PETMG R178) are noticeably more conical but continue to retain a pointed apex. The tribe Machimosaurini  is unique in that all members (Yvridiosuchus: OUMNH J.29850; Lemmysuchus: NHMUK PV R 3618; Machimosaurus: LMH 16387, LMH 16405, MG-8730-1, ONM NG 7, SMF 2027, SMNS 91415) have conical teeth with blunt, rounded apices (state 1) throughout the entirety of the dentition.
As with the above character, the apices of the teeth are relatively smooth and unornamented aside from the enamel ridges that reach the tip of the apex (state 0) in most teleosauroids. This is the condition seen in Plagiophthalmosuchus (MNHNL TU515) 379. Number of sacral vertebrae: two (0) or three (1) (Fig. 43).
In most teleosauroids, the postacetabular (=posterior) iliac process is either anteroposteriorly shortened, robust and process-like (state 0) or anteroposteriorly expanded and mediolaterally thin, expanding it into a 'fanlike' shape (state 1), and is best seen in either lateral or medial view. In Charitomenosuchus (NHMUK PV R 3806), Neosteneosaurus (PETMG R178), Lemmysuchus (NHMUK PV R 3816) and Mac. mosae , state 1 is present, with the postacetabular process lengthened into a mediolaterally thin 'fan-like' shape. However, it is important to note that state 1 is a putative apomorphy of derived teleosauroids, and is not seen in basal taxa such as 473. Ornamentation (dorsal osteoderms), the pits are either small round to ellipsoid and very densely distributed (0), large round to ellipsoid and well separated (1), irregularly shaped with an extreme variation in size, with elongate pits present on the ventrolateral surface running from the keel to the lateral margin (2), or variable in both size, shape and length that radiate in a starburst pattern (3) (Fig. 51).
While the overall shape of the dorsal osteoderms is consistent in certain areas of the body across taxa, the ornamentation (or pitting) pattern differs, most notably in the thoracic/sacral osteoderms. In most teleosauroids, the pits are large, subcircular to ellipsoid in shape, and generally well separated from one another. This condition (state 1) is seen in Plagiophthalmosuchus (NHMUK PV OR 14792), Mycterosuchus (NHMUK PV R 2617), Charitomenosuchus (NHMUK PV R 3806) and Neosteneosaurus (NHMUK PV R 2865; NHMUK PV R 3701; PETMG R178). In Charitomenosuchus (NHMUK PV R 3806), the pits are arranged in a semi-circular pattern, and the larger ones are situated more towards the lateral margins of the osteoderm. In Neosteneosaurus (NHMUK PV R 2865), most pits are exceptionally large (especially situated in the centre of the osteoderm), subcircular and fewer in number. While the osteoderm ornamentation in the holotype of Macrospondylus (MMG BwJ 595) is poorly preserved, the pits appear to be large and semi-ellipsoid with a strong anteroposterior keel. The pits also appear to be more closely placed to one another, which is observed in other Macrospondylus specimens (e.g. MMG BwJ 565; SMNS 51563; SMNS 51753), with a thin ridge separating them. In two teleosauroid taxa, the ornamental pits are small, round, and extremely densely distributed throughout the entirety of the dorsal osteoderms (state 0). This is seen in Platysuchus (SMNS 9930) and Teleosaurus (NHMUK PV R 119a). Certain teleosauroids, however, possess thoracic/sacral osteoderms with exceptionally enlarged, elongated pits; due to this elongation and large size, these pits merge with one another and become elongated grooves, especially along the lateral margins, with the pits radiating distally in a 'starburst' pattern (state 3). The remainder of the pits are variable in size (from small to large), irregularly shaped, and relatively close together. In addition, well-developed keels are generally present in these osteoderms. This condition is observed in machimosaurins (Lemmysuchus: NHMUK PV R 3618; Machimosaurus: ONM 1-25, SMNS 91415, Young et al., 2014). State 2, in which the pits are all irregularly shaped with extreme variation in size and have no 'starburst' pattern, is not present in any known teleosauroid taxa.

Most parsimonious unweighted strict consensus
The initial New Technology search recovered 125 most parsimonious trees (MPTs) of 1,659 steps (ensemble consistency index (CI) = 0.405; ensemble retention index (RI) = 0.844; ensemble rescaled consistency index (RCI) = 0.342; ensemble homoplasy index (HI) = 0.595) (Fig. 59A). With TBR branch swapping set to 100, 260 MPTs and 1,659 steps were recovered; when set to 1,000, 2,740 MPTs and 1,659 steps were found, with the best score hitting 301 out of 1,000 times. The overall topology did not change, with or without TBR.
In this topology, Eopneumatosuchus colberti Crompton & Smith, 1980, was found to be the immediate outgroup to Thalattosuchia, which was divided into two groups: Metriorhynchoidea and Teleosauroidea. Within Teleosauroidea, Plagiophthalmosuchus was recovered as the basal-most teleosauroid. This is weakly supported, with a jackknife percentage of 66% and a Bremer support value of 1. There are two main teleosauroid families recovered (see discussion on clades below), with the taxa Clovesuurdameredeor and Macrospondylus (which form a separate polytomy) being most closely related to both of them. Within the first family (Family T) (Fig. 59A), I. kalasinensis, I. potamosiamensis, the Chinese teleosauroid (IVPP V 10098) and Mystriosaurus are unresolved with one another and are most closely related to two remaining subfamilies (see below). The taxa Teleosaurus and Platysuchus are each other's closest relatives, with a Bremer support value of 2 and jackknife percentage of 54%. Interestingly, Mycterosuchus, Aeolodon, Bathysuchus and Sericodon form a distinct subfamily. Bathysuchus and Sericodon are sister taxa (Bremer support value of 3 and jackknife of 88%); Aeolodon is most closely related to Sericodon+Bathysuchus, and Mycterosuchus is most closely related to Aeolodon+Bathysuchus+Sericodon.
Within the second family (Family M) (Fig. 59A), there are multiple unresolved areas. Seldsienean, Deslongchampsina and Charitomenosuchus are unresolved from one another and are situated at the base of this clade (Bremer support value of 1 and jackknife of 66%). Most notably, there is a large polytomy including Pr. heberti, Pr. cf. bouchardi, Neosteneosaurus, S. rostromajor, Andrianavoay, Lemmysuchus and Yvridiosuchus, and Machimosaurini is not recovered as a monophyletic subgroup. However, when S. rostromajor is removed from the analysis (176 MPTs and 1,659 steps: CI = 0.405, RI = 0.844), Machimosaurini becomes a distinct group, with Lemmysuchus+Yvridiosuchus and Machimosaurus separated from Neosteneosaurus, Pr. heberti, Pr. cf. bouchardi and Andrianavoay (Fig. 59B). In addition, when both S. rostromajor and Andrianavoay are removed (167 MPTs, 1,659 steps: CI = 0.405, RI = 0.844), Pr. heberti and Pr. cf. bouchardi are unresolved from one another but separated from Neosteneosaurus, which by itself becomes most closely related to Machimosaurini. In all iterations (with or without the removal of S. rostromajor and Andrianavoay), the genus Machimosaurus forms its own subgroup, and relationships between the four species are mostly resolved. Machimosaurus mosae and Mac. buffetauti are unresolved from one another; and Mac. rex and Mac. hugii are sister taxa (with Mac. mosae+Mac. buffetauti being most closely related to them).

Most parsimonious unweighted consensus-majority rules
A parsimonious majority rules topology was produced to evaluate if there were any major changes from the strict consensus. The overall interrelationships within Teleosauroidea are more resolved than in the strict consensus topology (Fig. 59C), particularly within Family M. In Family T (Fig. 59C), I. kalasinensis is most closely related to the remaining taxa, and I. potamosiamensis and the Chinese teleosauroid (IVPP V 10098) are sister taxa, with Mystriosaurus being most closely related to them. In Family M (Fig. 59C), Clovesuurdameredeor is situated at the base of this group, in stark contrast to its initial positioning, and Deslongchampsina, Charitomenosuchus and Seldsienean are all separated. A new subfamily (consisting of Pr. heberti, Pr. cf. bouchardi, Andrianavoay, Neosteneosaurus, S. rostromajor and Machimosaurini) is clearly defined (100%), and Deslongchampsina is most closely related to this subfamily. Proexochokefalos heberti is most closely related to Pr. cf. bouchardi+Neosteneosaurus +S. rostromajor+Andrianavoay+Machimosaurini. Proexochokefalos cf. bouchardi, Neosteneosaurus, S. rostromajor and Andrianavoay are all unresolved from one another, and are most closely related to Machimosaurini. Unlike the strict consensus topology (when all taxa are included), Machimosaurini is relatively well-supported (73%); Lemmysuchus and Yvridiosuchus (unresolved from one another) are separate from Andrianavoay, Neosteneosaurus and S. rostromajor, and are at the base of Machimosaurini. Machimosaurus buffetauti and Mac. mosae are separated, with Mac. mosae being the more closely related to Mac. rex and Mac. hugii (which are sister taxa) than Mac. buffetauti. It is important to note that when S. rostromajor is removed from the majority rules consensus, there is no change to teleosauroid interrelationships.

Most parsimonious weighted strict consensus
As outlined above, the analysis was run once more using extended implied weights (k = 12). Extended implied weights (EIWs) are often used to improve the quality and stability of the results, and are more beneficial for palaeontological datasets than implied weights, which only introduces bias against characters with too many missing scores (Goloboff, 2014). The New Technology search (engines tailored as above) with TBR branch swapping resulted in 47 MPTs and a score of 48.94448. Due to relative clarity in the results, this is the topology referred to when formally naming clades (see below).
S. rostromajor and Andrianavoay. This is similar to the original consensus rather than the majority rules topology.
Deslongchampsina is once again found to be most closely related to the subfamily containing Pr. heberti, Pr. cf. bouchardi, S. rostromajor, Andrianavoay and Machimosaurini. Proexochokefalos cf. bouchardi and Pr. heberti are sister taxa, as in the majority rules topology. When S. rostromajor is removed, (Fig. 60B), the only change results in Machimosaurini being consistently recovered, as Yvridiosuchus and Lemmysuchus are separated from Neosteneosaurus and Andrianavoay. Interrelationships within Machimosaurus taxa were identical to the majority rules topology: Mac. hugii and Mac. rex are sister taxa, and Mac. mosae is most closely related to Mac. hugii+Mac. rex than Mac. buffetauti.
There are possible explanations as to why the tribe Machimosaurini remains unresolved from certain non-machimosaurins when all taxa are included. Firstly, both S. rostromajor and Andrianavoay are both represented by fragmentary skull material (and therefore scored for a low amount of characters), which may contribute to the lack of resolution. Another crucial factor is the lack of postcranial material for Andrianavoay, S. rostromajor and Yvridiosuchus; machimosaurins have a very distinct postcranium (Hua, 1999;Johnson et al., 2017), which may influence the appearance of the topology. Thirdly, there are no autapomorphies observed in S. rostromajor, which is a poorly preserved section of undiagnostic rostrum (see Johnson, Young & Brusatte, 2020, for more information). This may contribute to the uncertainty of its placement as either an intermediate non-machimosaurin (e.g. Neosteneosaurus) or basal machimosaurin (e.g. Yvridiosuchus).

Agreement subtree
The maximum agreement subtree (which chooses a subset of species with an equivalent restricted tree in all given evolutionary circumstances; Amir & Keselman, 1997), for Teleosauroidea was also produced (Fig. 60C) from the unweighted strict consensus: Plagiophthalmosuchus was recovered as the basal-most teleosauroid, and Families T and M were resolved. In Family T, Teleosaurus+Platysuchus and Mycterosuchus+ Bathysuchus+Aeolodon+Sericodon were recovered as monophyletic subclades. In Family M, Macrospondylus was situated at the base and Deslongchampsina was most closely related to Pr. cf. bouchardi + Neosteneosaurus + Machimosaurini. Surprisingly, Pr. cf. bouchardi was recovered at most closely related to Neosteneosaurus + Machimosaurini. Machimosaurus rex and Mac. hugii were also recovered as sister taxa, and Mac. buffetauti was most closely related to them. Lemmysuchus was situated at the base of Machimosaurini, with Neosteneosaurus as the closest relative. Therefore, the taxa identified as hypothetically responsible for poor resolution (not included in the agreement tree) were Indosinosuchus, Mystriosaurus, the Chinese teleosauroid, Clovesuurdameredeor, Charitomenosuchus, Seldsienean, S. rostromajor, Andrianavoay, Pr. heberti, Yvridiosuchus and Mac. mosae. This is logical, as most aforementioned taxa either are fragmentary, lack postcrania or are represented by a low number of specimens (excluding Charitomenosuchus). As mentioned previously, these are key factors that can lead to polytomies and lack of resolution in trees. However, it is interesting to note that Pr. cf. bouchardi is included in the agreement subtree as a stable taxon, even though it is a partial skull scored based off specimen photographs.

Bayesian results
As mentioned previously, three repetitions of MrBayes were run using the following functions: (#1) standard (rates = equal); (#2), gamma distribution (rates = gamma); and (#3) gamma distribution with variability (1set applyto = (1) coding = variable). The standard Bayesian results (#1) are relatively similar to those found in the implied weighting parsimony topology (standard deviation = 0.015520; harmonic mean = -8131.53). Teleosauroidea is monophyletic, Plagiophthalmosuchus is the basal-most teleosauroid and both Families T and M are recovered. However, there are slight differences within both subclades. In Family T, Platysuchus and Teleosaurus (sister taxa) are unresolved with Mycterosuchus+relatives and the East Asian teleosauroids+Mystriosaurus, and the East Asian teleosauroids (much like in the strict consensus and majority rules topologies), and I. potamosiamensis is most closely related to the Chinese teleosauroid+Mystriosaurus. In Family M, Pr. cf. bouchardi and Pr. heberti are not sister taxa, but rather Pr. cf. bouchardi is found to be most closely related to Neosteneosaurus+Andrianavoay+ S. rostromajor+Machimosaurini.
In the gamma Bayesian test (#2), the results (standard deviation = 0.019863; harmonic mean = −7785.47) (Fig. 61) are similar to that seen in the standard Bayesian analysis, but with two differences: 1. Charitomenosuchus, Seldsienean and Deslongchampsina are in a polytomy; and 2. Pr. cf. bouchardi and Pr. heberti are in a polytomy.
The gamma variation MrBayes analysis (#3) (standard deviation = 0.017365; harmonic mean = −8130.41) produced a topology identical to that seen in the standard Bayesian analysis. In all Bayesian analyses, S. rostromajor is most closely related to Machimosaurini.

CLADES AND THEIR SYNAPOMORPHIES
Within this section, the synapomorphies uniting major clades are highlighted and discussed. A period and then the synapomorphic character state number follow the character numbers. We have decided to establish the clade names under both the ICZN Code and the International Code of Phylogenetic Nomenclature (hereafter referred to as the PhyloCode) to ensure nomenclatural stability. First the clade will be established under the ICZN Code, giving its diagnosis, then the clade will be established under the PhyloCode, giving its phylogenetic definition.
Teleosauroidea Geoffroy Saint-Hilaire, 1831 Classification note. Teleosauroidea is a 'family group' clade established under the ICZN Code, at the superfamily rank.
Nominal authority. The nominal authority is based on Article 36.1 of the ICZN Code (Principal of Coordination, applied to family group names).
Description. The superfamily Teleosauroidea is supported by multiple synapomorphies. These include absence of a sclerotic ring (163.0), postorbital medial to the jugal on the postorbital bar (173.0), straightened (sub-rectangular) anterior maxilla in palatal view (184.1), relatively reduced occipital tuberosities (203.1), paired ridges located on the medial ventral surface of the basisphenoid (223.1), a distinctly spatulate anterior dentary with the maximum width at the D3-D4 couplet (254.2), D3 occludes against the premaxillary-maxillary suture (331.0), coracoid with a fan-shape distal end and a triangular-shaped proximal end (402.1), a scapular blade as wide as or narrower than the glenoid region (405.1) and presence of caudal armour (493.0), as well as scoring the 'pholidosaurid beak' as inapplicable (47.-). One of these characters is new to the dataset, and another character (47) was re-written and re-scored. It is important to note that in teleosauroids, certain characters score differently than Pelagosaurus but are the same for other basal metriorhynchoids (e.g. Teleidosaurus). These include a slightly convex or flat frontal (121.0), a broadly curved anterior margin of the external mandibular fenestra (260.0), and well-defined apicobasally aligned ornamental ridges on the dentition (357.4), Comments. Geoffroy Saint-Hilaire (1831: 34) initially defined teleosauroids (interpreted as 'Teleosauridae') as a distinct clade, referring to "un cachet crocodilien" ("a crocodilian Figure 61 Simplified consensus topology in MrBayes. Simplified consensus topology, produced in MrBayes using gamma distribution (rates = gamma), standard deviation = 0.019863, harmonic mean = −7785.47. Note that S. rostromajor is recovered as most closely related to Machimosaurini.
At the end of this description, Geoffroy Saint-Hilaire (1831: 37-38) writes 'Cette dernière combinaison remarquable dans les êtres téléosauriens devient des éléments caractéristiques pour une nouvelle famille; des éléments d'une puissance et d'une valeur à rendre en effet obligatoires les distinctions zoologiques de cette famille, c'est-à-dire l'érection des genres Téléosaurus et Sténéosaurus' ('This last remarkable combination in teleosaurs becomes characteristic elements for a new family; elements of power and value to make compulsory the zoological distinctions of this family, that is to say the erection of the genera Teleosaurus and Steneosaurus'). Geoffroy Saint-Hilaire (1831: 37) considered 'la région supérieure et vers la fin de l'arrière-crâne; et d'autre part le museau' ('the upper region and towards the end of the back of the skull; and (on the other hand) the snout'), along with 'le canal nasal et le palais' ('the nasal canal and the palat'), to be the most important features when distinguishing teleosauroid species. After Geoffroy Saint-Hilaire's (1831) work, teleosauroids continued to be traditionally grouped together based on their 'longirostrine' skull, dorsally directed orbits and high tooth count (Karl et al., 2008;Young & Andrade, 2009;Ballell et al., 2019). However, recent studies Foffa et al., 2019;Sachs et al., 2019a) have shown that there is more variation in the teleosauroid cranium than initially thought, and the shape of the skull and number of teeth cannot purely be relied on to define this clade.  -; 163.0; 173.0; 184.1; 203.1; 223.1; 254.2; 331.0; 402.1; 405.1; 493.0 (Figs. 60A and 60B). This unnamed clade shares one character with Neosteneosaurus and machimosaurins (nasals and maxillae are not elongated: 6.0) and one character with Mac. buffetauti and Mac. mosae (anteroposterior premaxillary length is less than 25% of total rostrum length: 43.0).
Nominal authority. The nominal authority is based on Article 36.1 of the ICZN Code (Principal of Coordination, applied to family group names).
Description. The subfamily Teleosaurinae consists of the genera Platysuchus and Teleosaurus, and there are four characters that unite them as sister taxa. These include both the tooth row and quadrate condyle being below the level of the occipital condyle but are unaligned with the tooth row at a lower level (2.5), the frontal-postorbital suture is lower than the intertemporal bar (131.1), densely distributed osteoderms with small round to ellipsoid pits (473.0), and presacral dorsal osteoderms are strongly curved (480.1). Comments. Vignaud (1995) initially diagnosed the subfamily Teleosaurinae as that containing Platysuchus and all Teleosaurus taxa. Here, Teleosaurus is currently limited to just one species, but follows the same proposal put forth in Vignaud (1995), in that Platysuchus is most closely related to Teleosaurus. Description. A number of synapomorphies, notably in the premaxilla, supports the subfamily Aeolodontinae, which includes the genera Mycterosuchus, Aeolodon, Sericodon and Bathysuchus. These include an '8'shaped premaxilla in anterior view (56.1), reduced basioccipital tuberosities (230.0), laterally oriented P1 and P2 (294.2), P1 and P2 do not form a couplet but are situated on the anterior margin of the premaxilla (295.1), P1 and P2 are both on the same transverse plane (298.1) and the anterior margin between the P2-P3 is sub-rectangular, with the P3 being clearly lateral to the P2 (299.1). Four out of six characters are new to this dataset.
Comments. Aeolodontinae is also always recovered as a monophyletic subclade, regardless of changing taxa and/or character scores and whether the dataset is run using parsimony or Bayesian criteria. It is interesting to note that, while similar in many aspects concerning the skull (namely the premaxillae), the postcranial material of Mycterosuchus differentiates vastly from other members of the group. For example, the proximal humerus is very strongly posteriorly deflected and hooked in Aeolodon, similar to members of Machimosauridae (e.g. Charitomenosuchus, Neosteneosaurus). In Mycterosuchus, the proximal humerus is also hooked, but weakly so, and is more clubshaped. The tuberculum and articular facet of the largest dorsal ribs are positioned directly in the middle, which is more similar to Charitomenosuchus and opposed to the medial edge position in Aeolodon. Other unique postcranial features to Mycterosuchus include a longer ulna than radius, an elongated pubic shaft, an enlarged anteromedial femoral tuber and the calcaneal tuber being approximately 25% larger than the astragalus (as discussed above). It is likely that the unique skull characteristics of these taxa are what is supporting this subfamily as monophyletic.
While postcranial materials of Aeolodon are well preserved in both specimens (NHMUK PV R 1086 and MNHN.F.CNJ 78), and partially preserved in Sericodon (see Schaefer, Püntener & Billon-Bruyat, 2018), it is important to note that there are no postcranial bones of Bathysuchus currently recorded. A full, comprehensive comparison of the postcrania of Aeolodon and Sericodon is essential, to examine if Sericodon possesses a reduced appendicular skeleton similar to that seen in Aeolodon, which has been hypothesized to be more pelagic than other teleosauroids (see below, as well as Foffa et al. (2019)).
Phylogenetic definition. The largest clade within Teleosauroidea containing Aeolodon priscus but not Indosinosuchus potamosiamensis and Teleosaurus cadomensis. This is a maximum-clade, or stem-based, definition. Description. The family Machimosauridae is united by a number of characters; these include the dorsally oriented external nares (34.1), the premaxillary anterior and anterolateral margins are not sub-vertical and do not extend ventrally (48.0), the premaxilla-maxilla suture is sub-rectangular and slightly interdigitating (most noticeably near the midline) (58.1), no anterolateral expansion of the supratemporal fenestrae (103.0), the postorbital excluded from the orbit posteroventral margin (158.0), mostly horizontal pterygoid with a distinct posterolateral angle (198.1) and cultriform process of the basisphenoid exposed and bifurcates the pterygoids (225.1).
Phylogenetic definition. The largest clade within Teleosauroidea containing Machimosaurus hugii, but not Plagiophthalmosuchus gracilirostris and Teleosaurus cadomensis. This is a maximum-clade, or stem-based, definition.
Diagnostic apomorphies. 34. 1; 48.0; 58.1; 103.0; 158.0; 198.1; 225.1 Description. The subfamily Machimosaurinae is supported by a handful of characters including the supratemporal fenestra length being twice as long as the width (104.1), a shallow Meckelian groove (269.1), a sharply curved angular (270.1) and non-procumbent dentition throughout the entirety of the jaws (325.0). Two of these characters are new to the dataset. Comments. There are multiple features unique to the genus Machimosaurus; however, there is only one definitive character that is preserved in all species: a wider than higher rostrum (7.0). All ambiguous synapomorphies are found in both Mac. buffetauti and Mac. mosae, but are scored as (?) in Mac. hugii and Mac. rex due to lacking or fragmentary material. These synapomorphies include simple, straight-lined dentary neurovascular foramina (32.0), three premaxillary alveoli (288.3), the tuberculum and articular facet of dorsal ribs positioned halfway in the middle (395.{01}), scapula with a strongly concave anterior edge (406.1), and inapplicability of ch. 292-294, 297 and 300.
Using our updated dataset, we consistently recover the subfamilies Teleosaurinae and Aeolodontinae, regardless of changes and/or additions to the dataset. However, positions of certain taxa regularly change. For example Pr. cf. bouchardi is recovered as unresolved with other members of Machimosaurinae in the strict consensus topology; however, in the extended implied weighting topologies it is recovered as the sister taxon to Pr. heberti. With these degrees of uncertainty, the addition of new characters and teleosauroid taxa has only caused greater ambiguity in certain areas of the tree (especially in the unweighted consensus analysis). While it is undoubtedly important to carefully study, re-analyse and re-describe specimens, and discover new character data, the addition of new characters may not be the key in resolving these issues.
More importantly, one of the major problems is that a single specimen, usually skull material, represents many of these species, such as the Chinese teleosauroid (IVPP V 10098), Pr. heberti, Clovesuurdameredeor and Andrianavoay. In some cases, these specimens are well preserved and offer vital information (e.g. Pr. heberti), but there are certain ones that may be key intermediate forms but are too fragmentary to offer any substantial data (e.g. Andrianavoay). One contributing factor is that very little fossil prospection is taking place in localities where many of these specimens have been found (e.g. Toarcian outcrops in China, Bathonian locations in Madagascar, Upper Jurassic sites in Thailand). In addition, there are vast areas, particularly along the Gondwanan coasts of Africa and India, which have yielded promising material but have yet to be prospected properly (Phansalkar, Sudha & Khadkikar, 1994;Dridi & Johnson, 2019). This represents a unique opportunity for future work, and the discovery of additional material for existing species will offer a greater resolution into teleosauroid evolution during the Middle to Upper Jurassic and into the Lower Cretaceous.

Excluded taxa
Certain taxa were omitted from our analysis because (1) the holotype was either destroyed or could not be located or (2) said taxa did not possess any other current substantial material. For example, Machimosaurus nowackianus, a specimen comprising of the anterior dentary from Ethiopia, was reported being housed in the GPIT in Tübingen . After its initial description, many researchers attempted to locate it within the collection and were unable (recently, it has been reported as returned from loan in March 2017: R. Irmis, 2019, personal communication). There is one available photograph of the specimen , from Von Huene (1938 fig. 1-4); however, it was shown only in a slightly blurred dorsal view, but more importantly, due to the sheer incompleteness of the specimen and lack of characteristic features, we omitted this taxon from our dataset.
The taxon Steneosaurus deslongchampsianus Lennier, 1887, was excluded from our dataset because the holotype (comprising of skull and mandibular material) was destroyed in 1944 (Vignaud, 1995), and there was no other definitive existing material for this particular taxon; currently, line drawings are the only source of information available (see Saville, 1876;Lennier, 1887). While these are invaluable for research, we were wary to score an entire taxon using only drawings; there are many instances (especially during the 19th and early 20th centuries) where figures were either altered, drawn to include missing skeletal elements, or interpreted as similar to other taxa (Andrews, 1913). The holotype of Teleosaurus geoffroyi Eudes-Deslongchamps, 1868c was based on three mandibular fragments, which J.A. Eudes-Deslongchamps considered distinct due to '…un nombre sensiblement inférieur de dents' ('…a significantly lower number of teeth') than T. cadomensis (Vignaud, 1995: 181). However, this specimen (now considered an objective junior synonym of T. cadomensis: see Jouve, 2009) was also destroyed in 1944, and this distinguishing feature cannot be confirmed. In addition, two taxa were disregarded due to specimens simply being too fragmentary. First, the holotype of Steneosaurus rudis Sauvage, 1874 consisted of fragmentary pieces of the skull and mandible; it was part of the BHN2R collection, which was later closed in 2003, and it went missing. However, Vignaud (1995) suggested that, due to the robustness of the specimen, it could be referred to as Machimosaurus sp. The second example is Steneosaurus roissyi Eudes-Deslongchamps, 1869 (MNHN.RJN 130a-c), which consists of a fragmentary piece of the mandible; this material has no distinguishing characteristics and is therefore more apt to be referred to as Teleosauroidea indeterminate.
However, these characters are erroneous; firstly, in C. leedsi (NHMUK PV R 3320; NHMUK PV R 3806; BRLSI GP1770a-e), the antorbital fenestrae are very small, shallow and depression-like. In LPP.M.37, there is a small depression where the antorbital fenestrae should be located, similar to C. leedsi. Secondly, the crania of many C. leedsi specimens (e.g. NHMUK PV R 3320; NHMUK PV R 3806; PETMG R179) are dorsoventrally crushed, so the maxillae appear to be low; however, BRLSI GP1770a-e is three-dimensionally preserved, with the maxillae dorsoventrally high as in LPP.M.37. Lastly, it is unclear what longitudinal furrows Vignaud (1998) was referring to in C. leedsi; the interalveolar surface of the dentary (NHMUKL PV R 3320; NHMUK PV R 3806) is smooth, with anteriorly prominent lateral crenulations similar to LPP.M.35. If Vignaud (1998) was referring to the coronoid processes protruding into the dentary, these are quite large in both LPP.M.35 and C. leedsi (NHMUK PV R 3320). In addition, LPP.M.35 and LPP.M.37 are comparable to C. leedsi (NHMUK PV R 3320; NHMUK PV R 3806) in the following: 1. Frontal with few, circular pits that are largely concentrated in the centre of the bone; 2. Mediolaterally thin posterior processes of the nasals (similar to T. cadomensis); 3. Sub-rectangular supratemporal fenestrae; 4. Slender teeth with pointed apices and faint enamel ornamentation; and 5. All referred specimens are middle Callovian in age and are found in corresponding stratigraphic horizons.

No antorbital fenestrae;
3. Elongated, slender anterior process of the jugal; and 4. The P1 is oriented anteriorly and the P2 is oriented slightly medially (differs from Neosteneosaurus NHMUK PV R 3701). Therefore, S. depressus can tentatively be referred to as a subjective junior synonym of Pr. heberti. However, a thorough re-description of both specimens is needed and is beyond the scope of this article.
The final taxon, Steneosaurus hulkei (NHMUK PV R 2074) (Fig. 62C), was excluded from our dataset as its holotype likely represents a sub-adult individual. The vertebral neurocentral suture is visibly prominent in young modern crocodylians and gradually closes and disappears in adults, in the direction from the caudals to the cervicals (Brochu, 1996). In the S. hulkei holotype, the neurocentral sutures are clearly visible and well-developed in the posterior thoracic vertebrae, suggesting it was a juvenile or sub-adult. In addition, S. hulkei displays a mixture of features similar to those seen in Neosteneosaurus (NHMUK PV R 2865; PETMG R178) and differs from Charitomenosuchus (NHMUK PV R 3320, NHMUK PV R 3806) and Lemmysuchus (NHMUK PV R 3168), such as: 1. The cranium is overall more robust than Charitomenosuchus (NHMUK PV R 3320); 2. No antorbital fenestrae are present (differs from Charitomenosuchus (NHMUK PV R 3320, NHMUK PV R 3168) in which they are present); 3. A subcircular premaxilla-maxilla suture (differs from Charitomenosuchus (NHMUK PV R 3320), which has a strongly interdigitating, rectangular premaxilla-maxilla suture);

Ecomorphological diversity
Our new phylogeny clarifies key ecomorphological aspects of teleosauroids, some of which have briefly been discussed in the literature. The ecological structuring of teleosauroids was initially outlined by Hua (1997) and Hua & Buffetaut (1997) but was never discussed or published in detail. Massare (1987) and recently Foffa et al. (2018) characterized a variety of fossil marine reptiles based on features of the teeth, separating various taxa into dietary guilds. In Foffa et al. (2018), seven teleosauroid taxa were included in the analysis. The results showed that Machimosaurus and Lemmysuchus occupied the crunch guild, which is specialized for handling hard prey (e.g. turtles); the remaining taxa (Mycterosuchus, Charitomenosuchus, Neosteneosaurus and Proexochokefalos) fit into the pierce guild, hypothesized to prefer softer prey such as smaller fishes and squid.
There are a number of ecomorphotypes associated with certain teleosauroid taxa which exhibit a distinct pattern of appearance, and there are four well-sampled points during the Jurassic (Toarcian, Bathonian, Callovian and Kimmeridgian) in which specific patterns of ecomorphotypes emerge (see Table 1; Fig. 63). These ecomorphs can be generally defined based on skull shape (longirostrine, mesorostrine or brevirostrine), dentition (for possible feeding style) and additional osteological characters that relate to the environment (e.g. length of the limbs, placement of the orbits). Teleosauroid skulls are generally split into three different 'rostral morphs': longirostrine, mesorostrine and brevirostrine (Fig. 63A), which relate to the length of the rostrum. Longirostry (e.g. Mycterosuchus) is defined as the preorbital length being 70% or more of the basicranial length; mesorostry (e.g. Mystriosaurus) is the preorbital length being 55-70% of the basicranial length; and brevirostry (e.g. Mac. mosae) is the preorbital length being 55% or less than the basicranial length . This rostral classification is in turn affiliated with features of the teeth, which include overall size and shape of the teeth, shape of apices, and presence or absence of carinae and ornamentation. In addition to these 'rostral morphs', teleosauroid feeding ecology can be broadly categorized into two feeding 'guilds': specialist (a species that has a limited diet) or generalist (a species able to thrive on a wide variety of food sources), which can be inferred based on the shape, size and apices of their teeth (Feranec, 2007). Macrophagous/durophagous (feeding on hard prey items) is generally regarded as part of the generalist guild (Foffa et al., 2018), but for the purpose of this paper, we refer to it separately.
During the Toarcian, Plagiophthalmosuchus represented a longirostrine specialist (Figs. 63A and 63B), characterized by its laterally facing orbits, elongated snout and multiple thin, pointed, poorly ornamented teeth, and was likely purely piscivorous (Westphal, 1962). Macrospondylus represents a longirostrine generalist and Mystriosaurus is a mesorostrine generalist (a massive, less elongated skull with smaller supratemporal fenestrae and more robust teeth). A heavily armoured, semi-terrestrial longirostrine generalist form is found in Platysuchus, indicated by the extensive and tightly packed rows of dorsal osteoderms. It is difficult to discern which ecomorphotype the Chinese teleosauroid (IVPP V 10098) fits into, as no teeth are preserved. However, based on both anatomical and phylogenetic data, this taxon would hypothetically have filled a mesorostrine role, possibly a generalist, similar to Mystriosaurus (which is a logical assumption, given Mystriosaurus is a closely related taxon). By the Bathonian, basal teleosauroids with laterally oriented orbits had presumably become extinct (only being known from the Toarcian), with the Plagiophthalmosuchus ecomorph vacated (and possibly held by basal metriorhynchoids). However, a new ecomorphotype had evolved: the macrophagous/durophagous mesorostrine form, exhibited by Yvridiosuchus. A number of specific features, including enlarged supratemporal fenestrae, an extensive neurovascular system and blunt, conical teeth, characterized this ecomorphotype. The larger supratemporal fenestrae would have housed powerful adductor muscles for closing the jaw, and the robust, rounded teeth were advantageous for capturing a wider or more generalised range of prey . There has also been some speculation that the evolution of machimosaurin features may have been linked to the evolution of hard shells in turtles; however, this possible correlation is difficult to test, due to the overall extreme diversification and expansion of coastal marine ecosystems (M. Rabi, 2017, personal communication). In addition to the durophagous/macrophagous role, Seldsienean filled the longirostrine generalist niche; Deslongchampsina filled the niche of mesorostrine generalist; and Teleosaurus replaced Platysuchus as the longirostrine, semi-terrestrial generalist form. The possible ecomorphotypes for both Andrianavoay and Clovesuurdameredeor are currently uncertain; morphologically it is clear that they do not represent machimosaurins (e.g. lack two rows of maxillary neurovascular foramina in Andrianavoay; no enlarged supratemporal fenestrae in Clovesuurdameredeor). Most of the rostral material is missing from Clovesuurdameredeor, making it difficult to infer skull and dental morphology. The preserved rostral section (including the anterior and middle maxillae) of Andrianavoay has at least 20 maxillary alveoli preserved; due to its position on the phylogeny, it may possibly have been a mesorostrine generalist, similar to Neosteneosaurus.
In the mid-Callovian, the ecomorphotypes within this ecological hierarchy did not change. Lemmysuchus represented a mesorostrine macrophagous/durophagous form; Charitomenosuchus became the longirostrine generalist; Neosteneosaurus and Pr. heberti both filled the role of mesorostrine generalist; and Mycterosuchus represented the longirostrine, semi-terrestrial ecomorphotype. However, in the Kimmeridgian, there was another major shift in ecomorphotype variation. The macrophagous/durophagous form became the most dominant ecomorph, with representatives in Mac. buffetauti, Mac. mosae (both brevirostrine) and Mac. hugii (mesorostrine). The semi-aquatic longirostrine generalist ecomorph disappeared, and the mesorostrine generalist, represented by Pr. cf. bouchardi, became extremely rare. In addition, another new ecomorphotype evolved: a longirostrine, semi-pelagic generalist form, represented by a handful of genera (Aeolodon, Bathysuchus and Sericodon). During the Upper Jurassic (the exact time is unknown), Indosinosuchus represented a probable generalist, mesorostrine form; and in the Hauterivian-Barremian (132-121 Ma), Mac. rex embodied the macrophagous/ durophagous ecomorph, but all other teleosauroids had presumably disappeared.
As seen in extant crocodylian species, larger individuals tend to be dominant, with larger species occupying prime territories, although this is not an unbreakable rule, as interactions between Crocodylus rhombifer (Cuban Crocodile) and Crocodylus acutus (American Crocodile) in the Central Americas demonstrate (Targarona et al., 2010;Thorbjarnarson, 2010). It is hypothetical that machimosaurids, being larger and more generalist, were able to assert dominance over smaller teleosaurids if co-existing within the same ecosystem, and therefore occupied more prime territories. This could have acted as a selection pressure and driven the evolution of more specialised ecomorphotypes. This is similar to that seen in extant crocodylian subdivisions of West African ecosystems; the species Crocodylus suchus (West African Crocodile), Mecistops cataphractus (West African slender-snouted crocodile) and Osteolaemus tetraspis (African Dwarf Crocodile) do not inhabit similar bodies of water (Kofron, 1992;Velo-Antón et al., 2014), and with decreasing size, all species live in smaller waterways, with Osteolaemus being capable of terrestrial foraging. This could be similar to the hierarchy seen in South American caimans: Melanosuchus niger (Black Caiman), Paleosuchus palpebrosus (Cuvier's Dwarf Caiman), Caiman yacare (Yacare Caiman), Caiman crocodilus (Spectacled Caiman) and Caiman latirostris (Broad-Snouted Caiman) (Ross, 1998;Busack & Pandya, 2001;Rebêlo & Lugli, 2001;Vasconcelos et al., 2008).
An additional interesting factor is that, throughout time, there were never more than four ecomorphological 'guilds' within teleosauroids (Fig. 64). Mesorostrine generalists (e.g. Deslongchampsina) and longirostrine generalists (e.g. Charitomenosuchus) were consistently present until the Late Jurassic, whereas the basal longirostrine specialist (Plagiophthalmosuchus) was present only during the Early Jurassic. During the Kimmeridgian/Tithonian, there were only three ecomorphs present (Fig. 64) (macrophagous/durophagous, longirostrine pelagic, and mesorostrine generalist forms) with two of these (macrophagous/durophagous and longirostrine pelagic forms) being dominant while the third (mesorostrine generalist form) was much rarer. In addition,  noted that, during the Late Jurassic, there was a divide within the genus Machimosaurus between 'open-sea' Machimosaurus body-plans (i.e. Mac. hugii, as suggested by the enlarged paraoccipital processes for muscle attachment) and nearshore/ turbulent water body-plans (i.e. Mac. mosae). The overall reflection of teleosauroid nice partitioning highlights three main points: 1. There was a specific niche partitioning strategy among teleosauroids that lived during similar times; 2. The ecomorphological diversity of teleosauroids was generally stable through time until the Late Jurassic; and 3. After the Late Jurassic, there was a growing divide within Teleosauroidea between near-shore forms and increasingly open-sea species.

Biogeographical distribution
Throughout their approximately 70-million-year history, teleosauroids achieved near-global distribution. Numerous specimens have been found across both Gondwanan and Laurasian continents, having been reported from the UK and Europe (Eudes-Deslongchamps, 1867; Westphal, 1961Westphal, , 1962Andrews, 1909Andrews, , 1913Benton & Taylor, 1984;Johnson et al., 2017;Čerňanský et al., 2017;Foffa et al., 2019), Africa (Newton, 1893;De Lapparent, 1955;Buffetaut, Termier & Termier, 1981;Fara et al., 2002;Fanti et al., 2016;Jouve et al., 2016;Dridi & Johnson, 2019), Asia (Young, 1948;Liu, 1961;Martin et al., 2019), India (Owen, 1852;Phansalkar, Sudha & Khadkikar, 1994), Siberia (Efimov, 1982(Efimov, , 1988Storrs & Efimov, 2000), South America (Cortes et al., 2019) and potentially North America (Table 2). Von Huene (1927) described two dorsal vertebrae from the Upper Lias of Portezuelo Ancho in north-western Argentina and attributed them to Steneosaurus gerthi (Buffetaut, Termier & Termier, 1981;Gasparini & Fernández, 2005); however, these specimens are now referred to as Thalattosuchia indeterminate (Gasparini & Fernández, 2005). Despite this vast global dispersal, few studies have examined teleosauroid biogeography in detail. Buffetaut, Termier & Termier (1981) suggested a Laurasian and Gondwanan faunal connection between Tethyan Europe and the southern area of Africa (such as Madagascar) via an epicontinental seaway during the Early Jurassic. In the late Toarcian, the distribution of teleosauroids appear parallel to the ammonite Bouleiceras, which occurs in Portugal (Mouterde, 1953), Spain (Geyer, 1965), Chile, Argentina (Von Hillebrandt, 1973), Madagascar, Algeria and Morocco (Buffetaut, Termier & Termier, 1981), suggesting a marine connection from South America around Africa to the Tethyan area. In addition, Hua & Buffetaut (1997) hypothesized that teleosauroid distribution was similar to that of the Saltwater Crocodile (Crocodylus porosus) living amongst the Indian Ocean archipelagos. Based on the biogeography of the above fossil sites, it appears that teleosauroids primarily diversified and dispersed around the Tethys Sea (which was a productive area, consisting of many continental reef ecosystems : Stanley, 1988), and most species were concentrated around the Jurassic tropic belts. This is also consistent with climate data (Rees, Ziegler & Valdes, 2000;Jenkyns et al., 2012;Korte et al., 2015), which suggests rapid warm/cool events influenced by oceanic currents followed by warm conditions (26-30 C) during the Middle Jurassic, as well as overall minimal global climate change throughout the Jurassic, making the coastlines exceptionally productive. However, there are still three main problems which continue to limit our understanding of teleosauroid dispersal and distribution through time. Firstly, there is a substantial area where material is either missing or severely fragmentary, including the Tethys coast of Africa and the eastern coast of Africa (ranging from Ethiopia to Madagascar). Secondly, the lack of confident identification for the lost Chechen material (Aalenian), and the Indian (Toarcian and Callovian) and Chinese (Toarcian) specimens limits our knowledge of which species of teleosauroids were able to successfully disperse into these areas. Lastly, the South American record for teleosauroids is surprisingly non-existent, as they are known only from the Early Cretaceous (Cortes et al., 2019). As teleosauroids must have dispersed through multiple routes along the Jurassic coastlines, it would be logical that they were able to migrate into the South American area during this time. It is therefore essential that future research examines material from, as well as exploring more of, these areas. As with patterns in teleosauroid ecomorphology, genera within both families were established in different locations (see Table 2). Teleosauridae were restricted to Laurasian continents, with Teleosaurus, Aeolodon, Mystriosaurus and Bathysuchus known from the UK and Europe; Mycterosuchus from Britain and Germany; Platysuchus from Europe (Germany and Luxembourg); and Indosinosuchus and the Chinese teleosauroid (and possibly Teleosaurus) from Asia. Machimosauridae have an overall wider geographical span, ranging from the UK and Europe to northern Africa, Madagascar and possibly India, with machimosaurins in particular being prevalent in Africa. The phylogeny also shows that teleosauroids were able to distribute across the continent early in their evolution; Plagiopthalmosuchus, three teleosaurids (Mystriosaurus, Platysuchus, the Chinese teleosauroid) and one machimosaurid (Macrospondylus) were definitively present during the early Toarcian in five distinct localities.

Palaeoenvironment and the importance of freshwater teleosauroids
The majority of teleosauroid species are found in semi-aquatic or marginal marine (generally coastal and lagoonal) environments, and certain taxa are hypothesized to have lived in semi-pelagic (Aeolodon, Bathysuchus and Sericodon), semi-terrestrial (Mycterosuchus, Teleosaurus and Platysuchus) and open ocean (Mac. hugii) ecosystems (refer to Fig. 63C). However, three purely East Asian teleosauroids, the Chinese teleosauroid (IVPP V 10098) and two species of Indosinosuchus, are found in freshwater deposits Martin et al., 2016Martin et al., , 2019. This is intriguing, as no other teleosauroids are known from these types of deposits. In environmental terms, this is striking with reference to two points: (1) adult vs juvenile habitat preference; and (2) specific osteological features.
Some modern crocodylians, such as Cr. porosus (Saltwater Crocodile), often prefer different habitats depending on their age (juvenile/sub-adult vs. adult) (Read et al., 2004), which is often related to body size and food preference (Taylor, 1979;Magnusson, Da Silva & Lima, 1987). In general, adults are more common in estuary or brackish regions, whereas juveniles and sub-adults prefer freshwater ecosystems such as rivers or lakes. It is possible that teleosauroids adopted a similar pattern, with mature individuals frequenting semi-marine habitats, and hatchlings and juveniles in freshwater environments. However, small specimens of Macrospondylus (less than 1 m total length) have been found in the Posidonia Shale Formation from Holzmaden (e.g. SMNS 10,000), which consists of marginal marine sedimentological deposits. In addition, adult individuals of Cr. porosus (Webb, Manolis & Brien, 2010), Crocodylus acutus (American Crocodile) (Thorbjarnarson et al., 2006) and possibly Crocodylus siamensis (Siamese Crocodile) (Smith, 1931;Platt et al., 2006) have been known to thrive in both saltwater and freshwater ecosystems.
Certain osteological characteristics in mature individuals can also be indicative of preferential habitat. The Indian gharial (Gavialis gangeticus), which is confined to riverine ecosystems, has distinctive protruding eyes (= telescoped orbits) that aid in capturing fish (Whitaker & Basu, 1983). In gavialoids, these telescoped orbits are homoplastic and independently evolved twice, once in advanced Gryposuchus species (Gr. colombianus and Gr. croizati) from South America, and once in Asian Gavialus (Salas-Gismondi et al., 2016). The depositional settings in which these taxa are found are fluvial-dominated paleoenvironments, which suggests that well-developed telescoped orbits are correlated with riverine ecosystems (Salas-Gismondi et al., 2016). In teleosauroids, Indosinosuchus potamosiamensis displays distinctive telescopic orbits (although not as widely separated as Gavialis) and is found in freshwater deposits (Martin et al., 2019), similar to Gryposuchus species. It would therefore be logical to assume that Indosinosuchus kalasinensis, from the same deposits, would also have had telescoped orbits; however, the skull (PRC-239) is slightly dorsoventrally crushed, making this confirmation difficult. Interestingly, Mycterosuchus nasutus, and more subtly Teleosaurus cadomensis, have telescoped orbits; it is thus hypothesized that these two taxa may have also preferred riverine/fluvial areas rather than marginal marine ecosystems.
In other fossil crocodylomorphs, the dyrosaurid Acherontisuchus guajiraensis Hastings, Bloch & Jaramillo, 2011 is hypothesized to have inhabited calmer, fluvial waters than other Old World dyrosaurids. The slender and narrow ischial shaft of this taxon had reduced surface area for attachment surfaces of the m. rectus abdominis and m. ischiopubis, which are responsible for respiration and pitch control in water (Hastings, Bloch & Jaramillo, 2011). The ischial shaft in teleosauroids is not as narrow or elongated as in dyrosaurids; the ischial shaft of the supposed fluvial I. potamosiamensis (PRC-27: Martin et al., 2019) does not look particularly different from the majority of teleosauroids (e.g. Charitomenosuchus, Neosteneosaurus), excluding machimosaurins (e.g. Lemmysuchus). In addition, the sedimentology (Cerrejón Formation, Colombia) along with associated flora and fauna, suggest that A. guajiraensis lived in a freshwater habitat. All specimens of A. guajiraensis are mature individuals, with specimens ranging from 4.6 to 6.4 m in length (Hastings, Bloch & Jaramillo, 2011). Adult specimens of the pholidosaurids Sarcosuchus, Elosuchus and Meridiosaurus are also thought to have inhabited freshwater ecosystems (Fortier, Perea & Schultz, 2011). Therefore, it is possible that mature teleosauroids did indeed frequent freshwater ecosystems, but solely in eastern Laurasian regions. More discoveries are needed from freshwater deposits in Europe to test whether many marginal marine teleosauroids were solely marine taxa.
One additional salient feature of teleosauroids is the position of the external nares. They are described as being either anterodorsally (e.g. in Indosinosuchus) or dorsally (e.g. in Deslongchampsina) oriented. However, in Mystriosaurus, the external nares are directed anteriorly (Sachs et al., 2019a). This is intriguing, as this positioning would not be practical for a semi-aquatic lifestyle. It is hypothetical that, due to this unusual placement of the external nares, Mystriosaurus was more terrestrial, or spent a greater amount of time on land, than other teleosauroids. Indeed, this example shows just how possible it is that some teleosauroids were, in actuality, not particularly well suited for living in water.

Teleosaurids vs. machimosaurids
In terms of morphology and ecology, teleosaurids are more phenotypically plastic than machimosaurids (see Fig. 63). They display three distinct ecomorphs (mesorostrine generalist, longirostrine pelagic specialist and longirostrine semi-terrestrial generalist) and potentially occupied four environmental habitats (semi-marine, pelagic, freshwater and semi-terrestrial). In contrast, machimosaurids seem to display an almost linear pattern: basal machimosaurids (e.g. Macrospondylus) are longirostrine, semi-marine generalists; more derived machimosaurines (e.g. Deslongchampsina, Proexochokefalos) are mesorostrine, semi-marine generalists, with more robust teeth; and machimosaurins (e.g. Lemmysuchus, Machimosaurus) are large-bodied, durophagous, semi-marine taxa, with complex dentition and robust skeletons. In terms of abundance and geographical dispersal, teleosaurids appear to be less common than machimosaurids, and based on current knowledge, were restricted to Laurasia. Machimosaurids as a whole, particularly Macrospondylus, have high abundance, and decrease in numbers after the Callovian. During the Kimmeridgian, Machimosaurus was the most common teleosauroid genus, but was less abundant than other contemporaneous marine reptiles. The distribution of machimosaurids is generally in Sub-Boreal European and Gondwanan areas and their dispersal was expansive, with multiple occurrences found in the UK, Europe and Africa, and potentially India. However, there is a possible instance of them being found in Siberia (see above). It is possible that machimosaurids had larger ranges than contemporaneous teleosaurids, with teleosaurids being more specialized and therefore restricted to certain environments. These ideas, reinforced by the phylogeny, show that teleosauroids were without doubt much more diverse, in terms of morphology, ecology and geography, than previously thought.
An additional factor that differs between teleosaurids and machimosaurids is body size. Machimosaurids reached over 5 m in total length during the lower Toarcian (e.g. Macrospondylus; Westphal, 1961); they continued to get bigger in the Middle and Late Jurassic, and into the Cretaceous (with Mac. rex hypothesized to be around 7.15 m in total length; Young et al., 2016). Teleosaurids remained smaller in every ecosystem in which they co-existed with machimosaurids; only the taxa Mystriosaurus and Mycterosuchus came close to the body sizes of machimosaurids. It is possible that this difference in body size is related to territory, locomotor and thermoregulation performance, and food sources, as in modern crocodylians (Grigg et al., 1998;Elsworth, Seebacher & Franklin, 2003).

CONCLUSIONS
Despite an increase in morphological work within the past decade, the evolutionary relationships of teleosauroids are poorly understood and little studied, and thus their macroevolutionary patterns are rarely evaluated. One major issue is the genus Steneosaurus, which is often recovered as paraphyletic or polyphyletic in phylogenetic analyses. Following on our recent re-classification of Steneosaurus as a nomen dubium and an invalid genus (Johnson, Young & Brusatte, 2020), we herein presented an in-depth phylogenetic evaluation of Teleosauroidea. We firstly proposed the following changes to teleosauroid nomenclature, as a direct result of the invalidity of Steneosaurus: seven new generic names (Plagiophthalmosuchus, Clovesuurdameredeor, Seldsienean, Charitomenosuchus, Proexochokefalos, Andrianavoay and Neosteneosaurus) and one new species (Indosinosuchus kalasinensis); and the resurrection of three historical genera (Macrospondylus, Aeolodon and Sericodon). Secondly, we described 38 new characters and 19 additional characters that are important and distinctive in teleosauroid morphology and discussed how these characters differ between taxa. Thirdly, we listed the results of the phylogenetic analyses based on our updated H+Y data matrix, containing 153 taxa (including 27 teleosauroids) and 502 osteological characters. Our results showed that both parsimony and Bayesian topologies are relatively consistent with one another. Next, we propose and define the following taxonomic clades: the families Teleosauridae (re-defined) and Machimosauridae, and the subfamilies Aeolodontinae and Machimosaurinae (which includes Machimosaurini). Finally, we evaluated the ecomorphology and distribution of teleosauroids, based on our new phylogeny. Teleosauridae and Machimosauridae are morphologically distinct, with differing biogeographic distributions (Teleosauridae is Laurasian and Machimosauridae is Sub-Boreal European-Gondwanan), habitat preferences and feeding strategies. The phylogeny infers that the teleosaurids were overall more phenotypically plastic than machimosaurids, with an east-Asian freshwater clade, a nascent pelagic clade, and a heavily armoured clade; machimosaurids were dominant in terms of abundance and dispersal, with a linear pattern of morphological changes. By evaluating our updated phylogeny, it is clear that teleosauroids were, in terms of morphology, ecology and geography, more diverse than previously thought.