Brachiosauridae is a clade of titanosauriform sauropod dinosaurs that includes the well-known Late Jurassic taxa
Sauropod dinosaur diversity reached an apparent peak in the Late Jurassic (
A partial skeleton of a sauropod was discovered in 1934, during quarrying in Damparis, in the Jura department of eastern France (
Brachiosauridae is a clade of titanosauriform sauropods that spanned the Late Jurassic–Early Cretaceous (
The four cladograms are based on: (A)
Based on its brief description and limited illustration in
The village of Damparis (Jura, Franche-Comté) is located in the eastern part of France, near the city of Dole, almost halfway between Dijon and Besançon (
The red cross marks the place where the bones and teeth of the dinosaur were found. To the right of the cross, the path slightly turns left following the curvature of the original cliff visible in
The surrounding cliff did not progress since the 1930’s and marks the south-eastern limit of the quarry.
One of us (OM) revisited the quarry in 1999, 2015 and 2016, gathering new lithological observations and interpretations, collecting additional ammonite specimens, and producing a revised stratigraphy. Below is a synthesis of the geology and environment of the Damparis quarry, based on these new data and a critical review of the literature.
The fossil assemblage was found in a 12 m thick formation formerly named the
It is marked by a sedimentological truncation of the underlying undulating chalky limestone banks and underlined by a 2 cm-thick red clayey bed, the lowermost one of the sequence (Photo: O Moine). See
In detail, the limestone beds are 0.1 to 1.5 m thick and yield very few fossils. Naked-eye and thin-section observations reveal that their base may be characterised by a few centimetres of red clay flakes and centimetric-wavelength ripple-marks, overlain by woody debris, quartz grains, other dark crystals, and sometimes by crust-forming filamentous algae. All of these elements progressively disappear upward, shifting to a homogeneous micritic limestone with keyvugs, bird’s eyes structures, sparite-filled sheet cracks, and a few Foraminifera. Moreover, thin-sections produced from the base of the first limestone bed demonstrate that lateral textural changes occur. For example, along the southeastern cliff of the quarry (
Alternating clay beds are 1 to 20 mm thick and present a pink-to-red oxidized-iron derived colour. They are deposited on the smooth upper surface of the underlying limestone beds. These sharp transitions imply a certain degree of hardening of the upper surfaces of the limestone beds. Sieved samples from the basal clay bed reveal the presence of mica flakes, glossy and dull angular quartz grains, and woody debris in the 0.063–1 mm fraction, as well as more rounded quartz in the finer fraction (<0.063 mm). Despite slight variations in thickness and colour, all clay beds have the same characteristics.
The fossil discovery was located in a 50 cm thick lens that laterally pinched out into a clay bed. This lens was approximately 9 m long and at least 5 m wide, corresponding to the spatial dispersion of the bones (
Based on the average thickness of 0.7 m for the limestone bed compressed by the lens (
The fossil-bearing lens showed two different facies. A 15 cm thick conglomerate of fine grained ‘flooding gravel’ limestome lithoclasts, with a pink-to-red friable matrix of sand, clay and calcium carbonate, formed the base of the lens. A thin-section produced from matrix attached to one of the sauropod bones shows an irregularly coloured micritic cement embedding quartz grains and rounded limestone lithoclasts that contain bird’s eyes structures and Foraminifera. Both types of element show a brownish border derived from the cement, which
(1) Upper banks of the
According to the facies definitions of
A detailed account of the stratigraphic position of the
At Damparis, the
Cyclostratigraphy and ammonites zones according to
The sauropod specimen was distributed over an area of approximately 30 m2 (
Following the criteria of
Damage of non-biological origin is relatively limited. Bone surfaces are characteristic of: (1) the first abrasion degree (most of the long bones, a few small ones, and all vertebrae) or no abrasion, which suggests very short or no transport (
Damage of a biological origin is less obvious and, if any, also modest. Spiral fracturing has been noted on most of the appendicular elements, as well as some rib fragments. Based on the likely limited amount of transport and rolling, these fractures might result from trampling, chewing, or breakage by carnivorous taxa. Despite the presence of theropod teeth in the assemblage, no obvious tooth marks have been observed. Nevertheless, tooth marks are not commonly observed in reptilian fossil assemblages (e.g.,
The initial local context was a semi-restricted lagoonal environment subject to sporadic emersions in a regressive setting, leading to the formation of limestone beds. The deposition of the sauropod body occurred before the limestone surface was completely hardened, which led to the formation of a hollow. The regressive setting enabled the scavenging of the sauropod body by theropods. Such associations of sauropod skeletons and theropod teeth are indeed good markers of emersion (
During the subsequent transgression, a prevailing coastal environment of a semi-restricted lagoon, under the influence of brackish continental run-off and involving moderate water streams, led to the rapid burial and disturbance of the sauropod skeleton. Based on the heterogeneous facies of the sediment forming the lens, as well as its complicated colouration (possibly resulting from organic body fluids;
Finally, based on the original description of the fossil-bearing lens at Damparis by
The electronic version of this article in Portable Document Format (PDF) will represent a published work according to the International Commission on Zoological Nomenclature (ICZN), and hence the new names contained in the electronic version are effectively published under that Code from the electronic edition alone. This published work and the nomenclatural acts it contains have been registered in ZooBank, the online registration system for the ICZN. The ZooBank LSIDs (Life Science Identifiers) can be resolved and the associated information viewed through any standard web browser by appending the LSID to the prefix
(A–E) labial views, (F–J) mesial views, (K–O) lingual views; (A, F, K) DAM 1, (B, G, L) DAM 2, (C, H, M) DAM 3, (D, I, N) DAM 4, (E, J, O) DAM 5. Scale bar equals 20 cm.
(A) Left lateral view, (B) anterior view, (C) right lateral view; (D) posterior view. Abbreviations: cpol, centropostzygapophyseal lamina; di, diapophysis; cprl, centroprezygapophyseal lamina; espol, expanded spinopostzygapophyseal lamina; no, notch; ns, notch; pa, parapophysis; pn, pneumatic foramen; pocdf, postzygapophyseal centrodiapophyseal fossa; podl, postzygodiapophyseal lamina; poz, postzygapophysis; prz, prezygapophysis; ri, ridge; sdf, spinodiapophyseal fossa; spol, spinopostzygapophyseal lamina; sprl, spinoprezygapophyseal lamina. Scale bar equals 10 cm.
(A) Left lateral view, (B) right lateral view, (C) anterior view; (D) posterior view; (E) dorsal view. Abbreviations: acdl, anterior centrodiapophyseal lamina; cprf, centroprezygapophyseal fossa; cprl, centroprezygapophyseal lamina; nc, neural canal; pa, parapophysis; pcdl, posterior centrodiapophyseal lamina; pn, pneumatic foramen; ri, ridge; tprl, intraprezygapophyseal lamina. Scale bar equals 5 cm.
(A) Left lateral view, (B) right lateral view, (C) anterior view; (D) ventral view. Scale bar equals 5 cm.
Sauropoda |
Eusauropoda |
Neosauropoda |
Macronaria |
Titanosauriformes |
Brachiosauridae |
Damparis dinosaur |
French “ |
Damparis sauropod |
Brachiosauridae indet. |
‘French |
‘French |
(A) Right lateral view, (B) anterior view, (C) posterior view. Abbreviations: cprl/acpl, centroprezygapophyseal lamina or anterior centroparapophyseal lamina; nc, neural canal; pcdl, posterior centrodiapophyseal lamina; pn, pneumatic foramen; pocdf, posterior centrodiapophyseal fossa. Scale bar equals 5 cm.
(A) Dorsal view; (B) ventral view. Abbreviations: sv, sacral vertebrae. Scale bar equals 10 cm.
(A) Right lateral view; (B) posterior view; (C) anterior view. Abbreviations: acdl, anterior centrodiapophyseal lamina; cprl, centroprezygapophyseal lamina; di, diapophysis; pcdl, posterior centrodiapophyseal lamina; prdl, prezygodiapophyseal lamina. Scale bar equals 10 cm.
(A) Lateral view; (B) medial view. Abbreviations: ac, acromion; acr, acromial ridge; avp, acromial ventral process; gl, glenoid. Scale bar equals 10 cm.
(A) Lateral view; (B) medial view. Abbreviations: ac, acromion; acr, acromial ridge; avp, acromial ventral process; gl, glenoid. Scale bar equals 10 cm.
(A) Lateral view; (B) medial view. Abbreviations: gl, glenoid. Scale bar equals 10 cm.
(A) Anterior view; (B) lateral view; (C) posterior view; (D) proximal view (anterior towards top); (E) distal view (anterior towards top). Abbreviations: co, condyle; dpc, deltopectoral crest; ri, ridge. Scale bar equals 10 cm.
Several elements were incorrectly identified by
(A) Anterior view; (B) lateral view; (C) posterior view; (D) medial view; (E) proximal view (anterior margin towards top); (F) distal view (anterior margin towards top). Abbreviations: amp, anteromedial process; alp, anterolateral process; icr, interosseous crest; ol, olecranon. Scale bar equals 10 cm.
(A) Anterior view; (B) lateral view; (C) posterior view; (D) medial view; (E) proximal view (anterior margin towards top). Abbreviations: amp, anteromedial process; alp, anterolateral process; icr, interosseous crest; ol, olecranon. Scale bar equals 10 cm.
(A) Distal view; (B) medial view; (C) proximal view; (D) anterior view. Scale bar equals 5 cm.
The left ischium (DAM 34, which might be the undescribed ‘incomplete left pubis’ mentioned by
(A) Lateral view; (B) medial view; (C) proximal view (anterior towards top); (D) distal end view (anterior margin towards top). Scale bar equals 5 cm.
(A) Dorsal view; (B) lateral view; (C) ventral view; (D) medial view; (E) proximal view (anterior margin towards top); (F) distal view (anterior margin towards top). Abbreviations: mc I, articular surface for metacarpal I. Scale bar equals 5 cm.
(A) Dorsal view; (B) lateral view; (C), ventral view; (D) medial view; (E) proximal view (anterior margin towards top); (F) distal view (anterior margin towards top). Abbreviations: bp, bulge-like process. Scale bar equals 5 cm.
Element and specimen number | Plate/figure number |
---|---|
Tooth (DAM 1) | Plate I, fig. 4 |
Tooth (DAM 2) | Plate I, fig. 6 |
Tooth (DAM 3) | Plate I, fig. 5 |
Tooth (DAM 4) | Plate I, fig. 7 |
Tooth (DAM 5) | Plate I, fig. 8 |
Cervical vertebra (DAM 6) | Plate II, fig. 4 |
Cervical vertebra (DAM 7) | Plate II, fig. 2 |
Dorsal vertebra (DAM 8) | Plate III, fig. 4 |
Dorsal vertebra (DAM 9) | Plate II, fig. 5 |
Sacrum (DAM 32) | Plate III, fig. 1 |
Caudal vertebra (DAM 10) | Plate II, fig. 1 |
Right humerus (DAM 28) | Plate IV, fig. 1 |
Left ulna (DAM 30) | Plate IV, fig. 2 |
Right carpal (DAM 19) | Plate IV, fig. 4 |
Left metacarpal I (DAM 20) | Plate III, fig. 3 |
Left metacarpal II (DAM 21) | Plate IV, fig. 5 |
Left metacarpal III (DAM 22) | Plate IV, fig. 6 |
Right metacarpal III (DAM 24) | Plate IV, fig. 8 |
Left metacarpal IV (DAM 23) | Plate IV, fig. 7 |
Left manual phalanx I-1 (DAM 16) | Plate IV, fig. 10 |
Left manual phalanx II-1 (DAM 15) | Plate IV, fig. 9 |
Left manual phalanx III-1 (DAM 17) | Plate IV, fig. 11 |
Left manual phalanx IV-1 (DAM 18) | Plate IV, fig. 12 |
Right ischium (DAM 35) | fig. 5 |
Right femur (DAM 36) | Plate IV, fig. 15 |
Left tibia (DAM 37) | Plate III, fig. 2 |
Right fibula (DAM 39) | Plate IV, fig. 3 |
Left astragalus (DAM 11) | Plate IV, fig. 16 |
Left metatarsal I (DAM 12) | Plate IV, fig. 17 |
Left metatarsal III (DAM 14) | Plate IV, fig. 18 |
Measurements of the five teeth (DAM 1–5;
(A) Dorsal view; (B) lateral view; (C) ventral view; (D) medial view; (E) proximal view (anterior margin towards top); (F) distal view (anterior margin towards top). Abbreviations: fl, medial flange. Scale bar equals 5 cm.
Scale bar equals 5 cm.
Left manual phalanx I-1 (DAM16) in (A) dorsal view; (B) proximal view; (C) distal view. Left manual phalanx II-1 (DAM 15) in (D) dorsal view; (E) proximal view; (F) distal view. Left manual phalanx III-1 (DAM 17) in (G) dorsal view; (H) proximal view; (I) distal view. Left manual phalanx IV-1 (DAM 18) in (J) dorsal view; (K) proximal view; (L) distal view. Scale bar equals 5 cm.
An asterisk denotes a measurement based on an incomplete element.
Dimension | DAM 1 | DAM 2 | DAM 3 | DAM 4 | DAM 5 |
---|---|---|---|---|---|
Total apicobasal height of crown and root | 81 | 65* | 66* | 49* | 41* |
Apicobasal height of crown | 43 | 51 | 44 | 32 | 29 |
Maximum mesiodistal width of crown | 18 | 19 | 17 | 13 | 13 |
Mesiodistal width of crown at base | 14 | 15 | 14 | 11 | 11 |
Labiolingual width of crown at base | 13 | 13 | 12 | 10 | 9 |
Slenderness Index | 2.39 | 2.68 | 2.59 | 2.46 | 2.23 |
All measurements are in millimetres.
As in other neosauropods (
(A) Lateral view; (B) medial view. Abbreviations: act, acetabulum; pp, pubic peduncle. Scale bar equals 10 cm.
(A) Medial view; (B) distal view. Scale bar equals 10 cm.
(A) Medial view; (B) anterior view; (C) lateral view; (D) proximal view (anterior towards right). Abbreviations: act, acetabulum; fti3, origin site for M. flexor tibialis internus; ip, iliac peduncle; pp, pubic peduncle. Scale bar equals 10 cm.
DAM 2 has more prominently developed lingual grooves and, as was the case in DAM 1, groove depth is asymmetrical. As with DAM 1, denticles are present on one side of the crown, restricted to the apical third. A non-planar wear facet is present at the crown apex of DAM 3, but is restricted to one side of the tooth. As such, it lacks the apical wear facets that characterize the teeth of diplodocoids and many somphospondylans (
(A) Lateral view; (B) medial view. Abbreviations: act, acetabulum; fti3, origin site for M. flexor tibialis internus; ip, iliac peduncle; pp, pubic peduncle. Scale bar equals 10 cm.
(A) Anterior view; (B) posterior view; (C) distal view. Abbreviations: icr, intercondylar ridges. Scale bar equals 10 cm.
(A) Anterior view; (B) lateral view; (C) posterior view; (D) proximal view (anterior towards top); (E) distal view (anterior towards top). Abbreviations: cc, cnemial crest; lc, lateral condyle; mc, medial condyle; scc, second cnemial crest; tfi, tuberculum fibularis. Scale bar equals 10 cm.
The Slenderness Index (apicobasal length of the tooth crown divided by its maximum mesiodistal width) ranges from 2.23 to 2.68 (
(A) Right fibula in anterior view; (B) right fibula in lateral view; (C) right fibula in posterior view; (D) right fibula in medial view; (E) right fibula in proximal view (anterior towards top); (F) right fibula in distal view (anterior towards top); (G) left fibula in anterior view; (H) left fibula in lateral view; (I) left fibula in medial view. Scale bar equals 10 cm.
(A) Proximal view; (B) distal view; (C) lateral view; (D) posterior view; (E) anterior view. Abbreviations: ap, ascending process; pf, posterior fossa; pp, posterior process; ri, ridge. Scale bar equals 5 cm.
(A) Ventral view; (B) lateral view; (C) proximal view; (D) dorsal view; (E) medial view; (F) distal view. Scale bar equals 5 cm.
Measurements of the axial skeleton are provided in
Neural arch height was measured from the dorsal surface of the centrum up to the base of the articular surfaces of the postzygapophyses, and neural spine height from this point upwards. Note that the measurements of the widths of the sacral centra are based on Sv1 (measured posterior to sacral ribs) and Sv4.
Dimension | DAM 6 (Cv) | DAM 7 (Cv) | DAM 8 (Dv) | DAM 9 (Dv) | DAM 32 (Sv) | DAM 10 (Ca) |
---|---|---|---|---|---|---|
Centrum length (including condyle) | 423 | 230 |
220 | ∼120 | – | – |
Centrum length (excluding condyle) | 372 | 139 |
198 | ∼100 | – | 88 |
Anterior centrum height | – | 156 | 162 | 192 | – | 193 |
Anterior centrum width | – | 213 | 141 | 200 | ∼170 | 197 |
Posterior centrum height | 211 | 149 |
173 | 186 | – | 182 |
Posterior centrum width | 135 | 150 |
∼110 | 199 | 144 | 196 |
Total length of fused centra | – | – | – | – | 730 | – |
Neural arch height | 76 | 110 |
– | – | – | 80 |
Neural spine height | 215 | – | – | – | – | – |
Maximum mediolateral width across sacrum (including ribs) | – | – | – | – | 682 | – |
All measurements are in millimetres.
denotes a measurement based on an incomplete element.
The anterior tip of the prezygapophysis is not preserved, but it seems unlikely that much is missing. Even incomplete, it extends beyond the anterior margin of the non-condylar centrum. The centroprezygapophyseal laminae (CPRLs) are too incomplete to determine if they are bifid, as is the case in many diplodocoids (
The lateral surface of the neural arch, posterodorsal to the PCDL and ventral to the PODL, is excavated by a postzygapophyseal centrodiapophyseal fossa (POCDF), which is divided into a small ventral and larger dorsal opening. Small foramina appear to be present throughout the fossae. The postzygapophyses do not extend to the posterior margin of the centrum. The interpostzygapophyseal lamina (TPOL) is not preserved, and the centropostzygapophyseal laminae (CPOLs) are partly reconstructed. Unlike many rebbachisaurids (
The lateral surface of the neural spine, just dorsal to the PRDL and PODL, is excavated by a series of small fossae, which together form the spinodiapophyseal fossa (SDF). These fossae are aligned and curve posterodorsally, with a larger fossa situated further dorsally. A similar series of excavations is present in middle–posterior cervical vertebrae of
DAM 7 (
A middle dorsal vertebra (Dv) preserves a near-complete centrum and the base of the neural arch (DAM 8;
DAM 9 (
A middle–posterior dorsal centrum figured by
Numerous portions of thoracic ribs are preserved, mainly comprising shafts, but some preserve the lower portions of the rib head (DAM 41). No rib heads are complete enough to determine whether the posterior surface was excavated, as is the case in titanosauriforms (
The preserved sacrum (DAM 32) is slightly reconstructed in places, but comprises four fused sacral centra, the bases of the ribs of sacral vertebra 1 (Sv1), and three pairs of sacral ribs (Sv2–4) (
The ratio of the mediolateral width across the combined sacral vertebrae and ribs to the average anteroposterior length of a sacral centrum is 3.7. This is lower than the values of diplodocoids and most titanosauriforms, which tend to have ratios greater than 4.0 and 5.0, respectively (
The ventral surfaces of the centra are gently convex transversely, lacking ridges or fossae. The exposed anterior and posterior articular surfaces of the sacral centra are fairly flat. A moderately deep pneumatic foramen excavates the lateral surface of the centra of Sv1–2, and probably Sv3 too. The presence or absence of foramina within sacral centra appears to be fairly ‘plastic’ among sauropods (e.g.,
The first fully preserved sacral rib pair emanates from the anterior end of Sv2, projecting posterolaterally, but there is a significant contribution from the posterior end of Sv1 too. A similar pattern of dual vertebral contribution to the second pair of sacral ribs seems to be present in
The second preserved sacral rib pair emanates from the anterior end of Sv3, with a small contribution from Sv2. These sacral ribs project posterolaterally from Sv3, but the posterior deflection is not as developed as in the preceding pair. The third preserved sacral rib pair emanates from the anterior end of Sv4, with a small contribution from Sv3; they project almost entirely laterally. The complete sacral ribs are fused distally to form a sacricostal yoke, as in other derived eusauropods (
DAM 10 (
Although only the bases of the caudal ribs are preserved, they show that they were supported from below by a sharp ACDL and PCDL, as well as a PRDL, and that there was no PODL present. Whereas the presence of a prominent PRDL is fairly common within the anteriormost caudal vertebrae of eusauropods (
The neural canal is large at both its anterior and posterior openings, and has a dorsoventrally tall elliptical shape. A few small vascular foramina pierce the neural canal floor. Unlike diplodocids and some rebbachisaurids (
The scapulocoracoid is described with the long axis of the scapular blade held horizontally. Both scapulae are preserved (
Measurements of scapulae presented as left (DAM 25) then right element (DAM 26), and were taken with the long axis of the scapular blade held horizontally.
Element | Dimension | Measurement |
---|---|---|
Anteroposterior length | 1,333/1,335 | |
Acromion anteroposterior length | 427/428 | |
Acromion maximum dorsoventral height | 675/660 |
|
Scapular blade minimum dorsoventral height | 174/175 | |
Scapular blade maximum dorsoventral height | 294 |
|
Anteroposterior length | 300 | |
Dorsoventral height | 415 |
All measurements are in millimetres.
denotes a measurement based on an incomplete element.
As in most eusauropods, with the exception of many somphospondylans (
The right coracoid (DAM 27;
In articulation, the dorsal margin of the coracoid lies below the level of the scapular acromion plate, and is separated from the latter by a V-shaped notch, as is the case in all non-titanosaurian sauropods (
The right humerus (DAM 28;
Lengths of the anteromedial and anterolateral proximal arms of the ulna follow the protocol proposed by
Element | Dimension | Measurement |
---|---|---|
Proximodistal length | 1,330 | |
Proximal end maximum mediolateral width | 415 | |
Distance from proximal end to distal tip of deltopectoral crest | 630 | |
Midshaft mediolateral width | 161 | |
Midshaft anteroposterior length | 93 | |
Midshaft minimum circumference | 450 | |
Distal end mediolateral width | 355 | |
Distal end maximum anteroposterior length | 140 | |
Proximodistal length | 910 | |
Proximal end maximum mediolateral width | 321 | |
Proximal end maximum anteroposterior length | 247 | |
Anteromedial arm length | 229 | |
Anterolateral arm length | 170 | |
Distal end maximum mediolateral width | 134 | |
Distal end maximum anteroposterior length | 123* | |
Proximodistal length | 915 | |
Maximum proximodistal height | 45 | |
Maximum mediolateral width | 89 | |
Maximum anteroposterior length | 78 |
All measurements are in millimetres.
DAM 28 is a gracile element, with low proximal (0.31), midshaft (0.12) and distal end (0.27) mediolateral width to humerus length ratios, and an average value (Robustness Index of
In anterior view, the proximal margin is convex, and it lacks a prominently developed process for the attachment site of
The rugose proximal articular surface extends slightly onto the anterior surface of the humerus. However, the posterior surface of the proximal end is damaged, meaning that we cannot determine whether the humeral head formed a prominent posterior bulge, such as that seen in several macronarian taxa, including
The deltopectoral crest projects anteromedially. Although it is not as medially directed as the deltopectoral crests of many titanosaurs (
There is a flange-like ridge on the anteromedial margin, a short distance from the distal end, but it is difficult to ascertain how genuine a feature this might be, as both the medial and lateral surfaces have undergone some deformation in this region. Two well-developed and widely spaced condyles are present on the lateral two-thirds of the anterior surface of the distal end. As such, it retains the plesiomorphic condition, whereas there is a single, undivided condyle in derived somphospondylans (
Both ulnae are largely complete (
The ratio of the maximum diameter of the proximal end to ulna length is 0.35. This is similar to most eusauropods, although the ulna is much more robust in derived titanosaurs (
The radial fossa along the proximal half of the ulna is striated and rugose, but there is no prominent ridge or tubercle. The proximal processes continue distally as rounded ridges, and the posterior surface of the proximal half is gently concave transversely in between. There is a prominent, proximodistally elongate interosseus crest present on the anteromedial surface: this begins a little below midheight of the ulna, and extends down to a short distance above the distal end.
The posterior surface of the distal end is flat, lacking the ridge and groove structure present in some turiasaurs (
The complete right carpal (DAM 19;
All manual elements are described as if they were held in a horizontal position, rather than the
Dimension | McI | McII | McIII | McIV | I-1 | II-1 | III-1 | IV-1 |
---|---|---|---|---|---|---|---|---|
Maximum proximodistal length | – | 383 | 394 | 360 | 69 | 77 | 68 | 61 |
Proximal end maximum diameter | 145 | 105 | 105 | 98 | 85 | 96 | 92 | 71 |
Proximal end diameter perpendicular to maximum diameter | 69 | 74 | 71 | 85 | 63 | 49 | 44 | – |
Midshaft dorsoventral height | – | 43 | 48 | 36 | – | – | – | – |
Midshaft mediolateral width | – | 69 | 54 | 50 | 66 | 78 | 76 | 56 |
Distal end dorsoventral height | – | 68 | 73 | 56 | – | – | – | – |
Distal end mediolateral width | – | 116 | 102 | 96 | 82 | 88 | 88 | 71 |
All measurements are in millimetres.
In articulation, the metacarpus appears to have the derived eusauropod condition (
Only the proximal half of the left metacarpal I (DAM 20;
The left metacarpal II (DAM 21;
Both third metacarpals are largely complete in terms of length, but the left metacarpal (DAM 22;
Brachiosaurid taxa are emboldened.
Taxon and reference | Ratio |
---|---|
0.84 | |
0.87 | |
MfN MB.R.2093 (PD Mannion, pers. obs., 2012) | 0.87 |
0.95 | |
0.97 | |
0.98 | |
0.99 | |
1.00 | |
1.05 | |
1.08 | |
1.08 | |
1.09 | |
1.22 | |
1.43 | |
1.86 |
The left metacarpal IV (DAM 23;
Phalanx I-1 (DAM 16;
Although accentuated by dorsoventral crushing, phalanx II-1 (DAM 15;
Aside from being smaller, phalanx III-1 (DAM 17;
Phalanx IV-1 (DAM 18;
Although lost, the two ungual claws were figured in medial/lateral view by
The left ilium (DAM 33) preserves the incomplete preacetabulum, pubic peduncle and acetabulum (
An asterisk denotes a measurement based on an incomplete element. Note that the left ischium measurements are more reliable than those for the distorted right ischium.
Element | Dimension | Measurement |
---|---|---|
Anteroposterior length as preserved | 555* | |
Dorsoventral height as preserved | 518* | |
Anteroposterior length of pubic peduncle at base | 56 | |
Proximodistal length as preserved | 197* | |
Distal end anteroposterior length | 182 | |
Distal end maximum mediolateral width | 75 | |
Iliac peduncle anteroposterior length | 121 | |
Iliac peduncle mediolateral width | 72 | |
Proximal plate anteroposterior length | 183 | |
Pubic articulation approximate dorsoventral height | 277 | |
Proximodistal length | 765 | |
Iliac peduncle anteroposterior length | 139 | |
Iliac peduncle mediolateral width | 53 | |
Proximal plate anteroposterior length | 188 | |
Pubic articulation approximate dorsoventral height | 257 | |
Distal blade dorsoventral height | 85 | |
Distal blade mediolateral width | 40 |
All measurements are in millimetres.
The ilium becomes transversely thin around the area where the pubic peduncle and preacetabulum meet. This results in the anterior margin of the upper portion of the pubic peduncle forming a sharp ridge that continues anterodorsally along the preserved ventral margin of the preacetabulum, thickening anteriorly. The pubic peduncle is complete in terms of length, but most of its medial surface has been sheared off; although it is mediolaterally wider than anteroposteriorly long, it is not possible to determine its distal end morphology. It is oriented perpendicular to the long axis of the ilium, as in other titanosauriforms (
There is a poorly preserved distal end of a limb or pelvic bone (DAM 31) that is here interpreted as the distal end of a left pubis (
Both ischia are preserved (
The iliac peduncle is anteroposteriorly elongate relative to the anteroposterior length of the proximal plate (ratio =0.66), comparable to the values in several brachiosaurids (
The lateral ridge, for attachment of
The angle formed between the long axis of the shaft and the acetabular line (i.e., the straight line from the anterodorsal corners of the iliac and pubic peduncles) is greater than 80°, in contrast to most rebbachisaurids (
Aside from damage to the fibular distal condyle, the right femur (DAM 36) is fairly complete (
For the fibulae measurements, the first value represents the left element (DAM 40) and the second value the right element (DAM 39). An asterisk denotes a measurement based on an incomplete element.
Element | Dimension | Measurement |
---|---|---|
Proximodistal length | 1,460 | |
Distance from proximal end to distal tip of fourth trochanter | 670 | |
Midshaft mediolateral width | 239 | |
Midshaft anteroposterior length | 83 | |
Midshaft minimum circumference | 600 | |
Distal end maximum anteroposterior length as preserved | 160* | |
Distal end mediolateral width (tibial condyle) | 168 | |
Distal end mediolateral width (fibular condyle) | 210 | |
Proximodistal length | 860 | |
Proximal end maximum anteroposterior length | 160 | |
Proximal end maximum mediolateral width (excluding cnemial crest) | 291 | |
Transverse width of cnemial crest (measured along posterior surface) | 77 | |
Midshaft maximum diameter | 139 | |
Midshaft diameter perpendicular to maximum diameter | 65 | |
Distal end mediolateral width | 246 | |
Distal end maximum anteroposterior length | 116 | |
Proximodistal length | 870*/890 | |
Proximal end anteroposterior length | 213/221 | |
Proximal end maximum mediolateral width | 79/53 | |
Distance from proximal end to distal tip of lateral trochanter | 430/428 | |
Midshaft anteroposterior length | 93/95 | |
Midshaft mediolateral width | 55/50 | |
Distal end anteroposterior length | –/167 | |
Distal end mediolateral width | –/119 | |
Maximum proximodistal height | 102 | |
Maximum mediolateral width | 234 | |
Maximum anteroposterior length | 145 |
All measurements are in millimetres.
The femoral head projects dorsomedially, similar to a number of other macronarians (
The fourth trochanter is a well-developed structure, positioned on the medial margin of the posterior surface. It does not extend to femoral midlength, contrasting with most sauropods, but is similar to the condition seen in
The mediolateral width of the tibial to fibular condyle is 0.8. This low value is comparable to that of
The left tibia is complete (DAM 37;
As preserved, the proximal and distal ends are transversely elongate and anteroposteriorly compressed, but this has undoubtedly been accentuated by crushing. Although it might have been more anteriorly directed prior to crushing, the laterally directed cnemial crest clearly did not project entirely anteriorly. The lateral margin of the cnemial crest is slightly incomplete, meaning that we cannot determine whether it formed a triangular point or remained rounded. There is a ‘tuberculum fibularis’ (see
The anterior surface of the tibia is mainly gently convex transversely, becoming flat at the distal end. Both the anteromedial and anterolateral margins of the distal end form sharp ridges, but these are likely to have been accentuated, or even fully caused, by crushing. Although the medial distal condyle extends further distally than the lateral condyle, it is reduced and does not extend as far laterally. The mediolateral width of the distal end is less than twice that of the maximum diameter of the midshaft (ratio =1.77), contrasting with the expanded distal ends of many titanosaurian tibiae (
Both fibulae are preserved (
In lateral view, the fibula is straight, rather than having the sinuous morphology that characterizes many somphospondylans (
The lateral trochanter is a low and singular structure, with a gentle groove situated anteriorly. There is a slightly raised area anterior to this groove on the right fibula, but this is absent in the better preserved left fibula, suggesting that this morphology has been affected by crushing. As such, in contrast to many somphospondylans (
The anterior margin of the distal third forms a sharp ridge, and the elliptical-shaped distal end is expanded transversely (as well as slightly anteroposteriorly), with a well-developed medial, lip-like expansion. Distally, the fibula is twice as thick mediolaterally as the midshaft, as is the case in
The left astragalus (DAM 11;
The astragalus of
The ascending process extends to the posterior margin of the astragalus, a condition that characterizes Neosauropoda (
No calcaneum is preserved, but we cannot determine whether this is a genuine absence, or merely a taphonomic artefact. A calcaneum is present in most sauropods for which a well preserved lower hindlimb and metatarsus is known, but is lost in titanosaurs (
A left (DAM 12;
An asterisk denotes a measurement based on an incomplete element.
Dimension | MtI | MtIII |
---|---|---|
Maximum proximodistal length | 175 | 234 |
Proximal end maximum diameter | 109 | 123 |
Proximal end diameter perpendicular to maximum diameter | 95 | 42 |
Midshaft dorsoventral height | 39 | 28 |
Midshaft mediolateral width | 77 | 64 |
Distal end maximum dorsoventral height | 48* | 53 |
Distal end maximum mediolateral width | 120 | 75 |
All measurements are in millimetres.
The proximal end of metatarsal I has a D-shaped outline, with a concave lateral margin and a dorsolateral, tapered projection. This cross section is maintained along the proximal half, before there is a strong twist in the metatarsal axis distally. As in most eusauropods (
The distal end of metatarsal II is dorsoventrally tallest on its medial half. The lateral surface of the distal end slopes to face dorsolaterally, with the medial surface of the distal end of metatarsal III presumably resting on top of this surface. In contrast, the medial surface of the distal end is concave, with the dorsomedial margin forming a sharp ridge; the ventrolateral expansion of the distal end of metatarsal I fits into this concavity. The distal articular surface extends onto the dorsal surface of the metatarsal, but does not extend far proximally.
The metatarsal III to tibia length ratio is 0.27. In most non-titanosauriforms this value is less than 0.25 (
We have revised the scores for
Nineteen additional characters have been added to the data matrix, nine of which are novel to our study. The resultant data matrix comprises 77 taxa scored for 416 characters. Characters 1–397 are the same as those presented in previous iterations of the data matrix (
Humerus to femur proximodistal length ratio: 0.8 or less (0); >0.8 to <0.9 (1); 0.9–0.95 (2); >0.95 (3) (
Basioccipital, fossa on lateral surface, extending from base of occipital condyle to base of basal tubera: absent (0); present (1) (
Basicranium, cranial nerve opening II (optic foramen): single opening (0); medially divided to form two foramina (1) (
Surangular, anterior foramen: absent (0); present (1) (
Splenial, position of anterior end relative to mandibular symphysis: posterior to symphysis (0); participates in symphysis (1) (
Teeth, D-shaped crown morphology in labial/lingual view: narrows mesiodistally along its apical third (0); narrows mesiodistally along its apical half, giving it a ‘heart’-shaped outline (1) (new character: based on
Middle–posterior cervical neural arches, vertical midline lamina (part of the interprezygapophyseal lamina [TPRL]) divides the centroprezygapophyseal fossa (CPRF) into two fossae: absent (0); present (1) (new character: based on
Middle–posterior cervical neural arches, vertical midline lamina (part of the interpostzygapophyseal lamina [TPOL]) divides the centropostzygapophyseal fossa (CPOF) into two fossae: absent (0); present (1) (new character: based on
Middle cervical neural spines, lateral fossa at the base of the prezygapophyseal process bounded by SPRL, PRDL and PODL: absent (0); present (1) (
Middle and posterior cervical neural spines, lateral surface between PRDL, PODL, SPOL (i.e., the spinodiapophyseal fossa [SDF]), has 3 or more coels separated from each other by low ridges: absent (0) present (1) (new character: based on PD Mannion & P Upchurch, pers. obs., 2009–2013; see
Cervical ribs, anterior projection extends beyond anterior margin of centrum (including condyle): present (0); absent (1) (new character).
Sacral ribs, Sv2 ribs: emanate solely from Sv2 (0); emanate from Sv2, with a contribution from Sv1 (1) (new character; see
Anteriormost caudal centra, ACDL: absent, or represented by no more than a faint ridge (0); present, well defined or sheet-like (1) (
Anterior–middle caudal neural arches: spinopostzygapophyseal lamina (SPOL) shape: SPOL grades smoothly toward postzygapophyses (0); SPOL abruptly ends near the anterior margin of the postzygapophyseal facet, and postzygapophyses sharply set off from neural spine, often projecting as distinct processes (1) (
Anterior–middle caudal neural arches, anteroposteriorly oriented ridge and fossa (‘shoulder’) between prezygapophyses and postzygapophyses: absent (0); present (1) (
Radius, proximal to distal end anteroposterior length ratio: 0.5 or greater (0); less than 0.5 (1) (new character: based on
Ulna, vertical groove and ridge structure on posterolateral surface of distal shaft: absent (0); present (1) (
Carpal bones, distal carpal mediolateral width to anteroposterior length ratio: less than 1.4 (0); 1.4 or greater (1) (new character: based on
Metacarpal III, maximum mediolateral width to dorsoventral height of the proximal end ratio: less than 1.3 (0); 1.3 or greater (1) (new character; see
Tibia, tubercle (‘tuberculum fibularis’) on posterior (internal) face of cnemial crest: absent (0); present (1) (
Following previous analyses of iterations of this data matrix, characters 11, 14, 15, 27, 40, 51, 104, 122, 147, 148, 177, 195, 205 and 259 were treated as ordered multistate characters, and nine unstable and highly incomplete taxa (
The pruned data matrix was then analysed using the ‘Stabilize Consensus’ option in the ‘New Technology Search’ in TNT vs. 1.1 (
(A) Ventral view; (B) dorsal view; (C) lateral view; (D) medial view; (E) proximal view; (F) distal view. Scale bar equals 5 cm.
In contrast to
Character correlation via the non-independence of characters is a potentially problematic issue for any phylogenetic analysis. If a set of characters represents non-independent aspects of a single anatomical modification, then this feature will be over-weighted in the analysis, leading to a potentially biased topology.
Brachiosauridae is highlighted in red, and non-brachiosaurid taxa previously included in the clade are highlighted in blue. Note that this tree was produced following the
Brachiosauridae is resolved after the
Two other potentially interrelated characters highlighted by
Numerous authors have stressed the importance of serial variation in sauropod vertebrae (e.g.,
Excluding characters (that do not fully covary) because they are ‘biologically related’ is also problematic if these skeletal changes do not all occur at one node of the tree. For example, the ‘wide-gauge’ stance of titanosaurs seems to be the product of numerous anatomical changes, including the medial deflection of the proximal femur, increased eccentricity of the femoral shaft, and bevelling of the distal femur (
In summary, we argue that where there is variation, this should be captured, rather than ignored. We agree with the concern of
Comparisons with the topologies of two recent independent analyses (
Nearly all of these brachiosaurid taxa have been described in detail. Only the appendicular skeleton of
Following our revised analysis, Brachiosauridae is supported by the following synapomorphies: (1) presence of denticles on teeth (C113 (reversal)); (2) lateral fossa at the base of the prezygapophyseal process in middle cervical vertebrae (C403); (3) elongate and dorsoventrally narrow diapophyses in anterior–middle dorsal vertebrae (C154); (4) anterior dorsal neural spines that are dorsoventrally taller than posterior ones (C158); (5) middle–posterior dorsal neural spines with spinopostzygapophyseal laminae divided into medial and lateral branches (C165); (6) ribs of sacral vertebra 2 include a contribution from Sv1 (C406;
Consistent with previous iterations of this data matrix, the Late Jurassic German dwarf sauropod
Our
At least three of our new/revised scores result in
We are unsure why this difference in the position of
As noted by
Purported Middle Jurassic brachiosaurids have all been demonstrated to belong outside of Neosauropoda (
Brachiosaurid remains are known from the earliest Cretaceous of southern Africa (
There is currently no evidence that brachiosaurids ever reached Asia (
A detailed redescription of a long-neglected sauropod specimen from the middle–late Oxfordian (Late Jurassic) of eastern France recognises it as a distinct brachiosaurid,
Map modified after Cariou (2013). Abbreviated locations for: (1) truncations: O, Ornans (
Correlation scheme of the lithological units of Damparis with both synthetic geological successions of Franche-Comté region and of north-western Switzerland.
Taxon names and stratigraphical ranges have been updated from original publications and different sources respectively. Only two taxa (highlighted in yellow) are still affected by taxonomic vs. stratigraphic inconsistencies.
Brigham Young University, Provo, Utah, USA
Museo de la Fundacíon Conjunto Paleontológico de Teruel-Dinópolis, Aragón, Spain
Museo ‘Carmen Funes’, Neuquén, Argentina
Museum für Naturkunde Berlin, Germany
Museu da Lourinhã, Lourinhã, Portugal
Museo de Ciencias Naturales de Valencia, Spain
Muséum National d’Histoire Naturelle, Paris, France
Musée National du Niger, Niamey, Republic of Niger
Colección de Paleontología de Vertebrados de la Fundación Instituto Miguel Lillo, Tucumán, Argentina
Staatliches Museum für Naturkunde Stuttgart, Germany
The authors would like to thank both the Solvay group and Inovyn company for allowing fieldwork in the Damparis quarry, François Atrops and Raymond Enay from Lyon 1 University for the identification of the ammonites, and Elsa Cariou from Nantes University for stimulating discussion. We thank Y Després and V Pernègre for help in the cleaning and re-preparation of the specimens. Specimen photographs were taken by L Cazes of the MNHN, with collaboration of RA. We are also grateful to all of those who have helped with access to sauropod specimens in their care. José Carballido kindly provided us with additional information and photographs of
The authors declare there are no competing interests.
The following information was supplied regarding data availability:
The raw data has been supplied as a
The following information was supplied regarding the registration of a newly described species:
Vouivria: urn:lsid:zoobank.org:act:B06BCF72-56A8-4DD6-BC27-CC0BA6D0092D, damparisensis: urn:lsid:zoobank.org:act:CCAA960C-6A39-46A4-8AC9-70D8BA816647, Publication LSI: urn:lsid:zoobank.org:pub:5EB3AF68-A8A2-407D-BF1B-5F856C3B505D.