Vertebrate paleobiodiversity of the Early Cretaceous (Berriasian) Angeac-Charente Lagerstätte (southwestern France): implications for continental faunal turnover at the J / K boundary
Author
Allain, Ronan
Author
Vullo, Romain
Author
Rozada, Lee
Author
Anquetin, Jérémy
Author
Bourgeais, Renaud
Author
Goedert, Jean
Author
Lasseron, Maxime
Author
Martin, Jeremy E.
Author
Pérez-García, Adán
Author
Fabrègues, Claire Peyre De
Author
Royo-Torres, Rafael
Author
Augier, Dominique
Author
Bailly, Gilles
text
Geodiversitas
2022
2022-07-21
44
25
683
752
journal article
107849
10.5252/geodiversitas2022v44a25
d0184974-bea3-4f97-a2f8-98887ec4f87e
1638-9395
6902033
urn:lsid:zoobank.org:pub:EA12DCB7-A5BE-4763-B805-25087EBD726D
cf.
Cteniogenys
(
Fig. 16
A-E)
DESCRIPTION
A characteristic robust vertebra (
Fig. 16
A-C), as well as a smaller vertebra that probably belongs to a juvenile individual (
Fig. 16D, E
), have been discovered among the microremains. Both centra are amphicoelous, with an opened neurocentral suture. Dorsally, a distinct longitudinal ridge is laterally bordered by longitudinal grooves on the floor of the neural canal (
Fig. 16A
). In ventral view, the lower half of the centrum is pinched into a keel (
Fig. 16D
). The margins of the cotyle are thick (
Fig. 16E
). All these characters are reminiscent of choristoderan reptiles (
Evans 1991
;
Averianov
et al.
2006
;
Vullo
et al.
2014
;
Haddoumi
et al.
2016
;
Lasseron
et al.
2020
). ANG M-20 is nearly identical to the vertebra of
Cteniogenys
figured by
Evans & Milner (1994
: fig.18.5). Hence, it is here tentatively assigned to this genus, although this identification needs to be substantiated with additional material. These freshwater or amphibious diapsids are well known in Laurasia (
Matsumoto
et al.
2013
), but have also been reported from the Jurassic-Cretaceous transition of North Africa (
Lasseron
et al.
2020
). In the Lower Cretaceous of Asia, the diversity and abundance of choristoderans is particularly high in the faunal assemblages, in which crocodyliforms are scarce (
Matsumoto
et al.
2015
;
Skutschas & Vitenko 2017
). Conversely, the abundance and diversity of crocodyliforms at Angeac-Charente may explain the scaricity of choristoderans.