Wolf spider burrows from a modern saline sandflat in central Argentina: morphology, taphonomy and recognition of fossil examples
- Published
- Accepted
- Subject Areas
- Animal Behavior, Paleontology
- Keywords
- spider burrow, wolf spiders, neoichnology, predation, burrow reoccupation, burrow modifications, saline lake, sandflat, Gran Salitral, Pavocosa sp.
- Copyright
- © 2018 Mendoza Belmontes et al.
- Licence
- This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
- Cite this article
- 2018. Wolf spider burrows from a modern saline sandflat in central Argentina: morphology, taphonomy and recognition of fossil examples. PeerJ Preprints 6:e26674v1 https://doi.org/10.7287/peerj.preprints.26674v1
Abstract
Pavocosa sp. (Lycosidae) burrows found in an open sparsely vegetated area on the edge of the saline lake the “Gran Salitral”, in central Argentina, are described. Burrows were studied by capturing the occupant and casting them with dental plaster. The hosting sediments and vegetation were also characterized. Inhabited Pavocosa sp. burrows display distinctive features as open, cylindrical, nearly vertical, silk lined shafts about 120 mm long, subcircular entrances, a gradual downward widening, and a particularly distinctive surface ornamentation in the form of sets of two linear parallel marks at a high angle to the burrow axis. Instead, casts of vacated Pavocosa sp. burrows showed some disturbances caused either by the reoccupation by another organism or by predation of the dweller. Two morphologies are related to reoccupation of burrows: those with a structure in form of an "umbrella” and another with smaller excavations at the bottom of the burrow. Predation by armadillos produces funnel-shaped burrows. Both active and abandoned Pavocosa sp. burrow casts are compared with existing ichnogenera and its distinction is discussed. It is argued that key features like the presence of a neck, a downward widening and the surface texture will allow recognition of wolf spider burrows in the fossil record. Fossil wolf spiders are recorded since the Paleogene (possibly Late Cretaceous), so Cenozoic continental rocks can contain wolf spider burrows awaiting recognition. In addition, the particular distribution of Pavocosa sp. in saline lakes may imply that this type of burrows are linked to saline environments.
Author Comment
This is a submission to PeerJ for review.
Supplemental Information
Cast GHUNLPam-4771
Lenght =131 mm; Neck Lenght= 8mm; Minimum Diameter =15 mm; Maximum Diameter=22 mm; Angle=84º. Dweller captured (Pavocosa sp GHUNLPam-4770).
Cast GHUNLPam-4772
Lenght =115 mm; Neck Lenght= 5 mm; Minimum Diameter =15 mm; Maximum Diameter=18 mm; Angle=88º.
Cast GHUNLPam-4773
Lenght =130 mm; Neck Lenght= 6 mm; Minimum Diameter=16 mm; Maximum Diameter=27 mm; Angle=75º. Deweller captured (Pavocosa sp GHUNLPam-4770). Eggs sac found on the bottom.
Cast GHUNLPam-4774
Lenght =106 mm; Neck Lenght= 6 mm; Minimum Diameter =13 mm; Maximum Diameter=23 mm; Angle=72º. Sac of eggs found on the bottom.
Cast GHUNLPam-4775
Lenght =118 mm; Neck Lenght= 7 mm; Minimum Diameter =13 mm; Maximum Diameter=25 mm; Angle=85º.
Cast GHUNLPam-4776
Lenght =111 mm; Minimum Diameter =15 mm; Maximum Diameter=15 mm; Angle=86º; "Umbrella" Structure: Diameter= 47 x 59 mm.
Cast GHUNLPam-4777
Lenght =106 mm; Minimum Diameter =15 mm; Maximum Diameter=22 mm; Angle=78º."Umbrella" Structure Diameter= 54 x 66 mm
Cast GHUNLPam-4778
Cast GHUNLPam-4778. Lenght =116 mm; Minimum Diameter =15 mm; Maximum Diameter=22 mm; Angle=87º. Smaller burrows with around 33 mm lenght and 8 mm of diameter.
Cast GHUNLPam-4779
Lenght =130 mm; Minimum Diameter =12 mm; Maximum Diameter=100 mm; Angle=85º.