Caudata, Scopoli, 1777

Allain, Ronan, Vullo, Romain, Rozada, Lee, Anquetin, Jérémy, Bourgeais, Renaud, Goedert, Jean, Lasseron, Maxime, Martin, Jeremy E., Pérez-García, Adán, Fabrègues, Claire Peyre De, Royo-Torres, Rafael, Augier, Dominique & Bailly, Gilles, 2022, Vertebrate paleobiodiversity of the Early Cretaceous (Berriasian) Angeac-Charente Lagerstätte (southwestern France): implications for continental faunal turnover at the J / K boundary, Geodiversitas 44 (25), pp. 683-752 : 697

Caudata ? indet.

( Fig. 11 )

DESCRIPTION

Among the microvertebrates from Angeac-Charente, a specimen could be referred to Caudata. Indeed, the vertebra ANG M-71 ( Fig. 11 ) is anteroposteriorly elongated, with a broad, almost circular cotyle ( Fig. 11A ) and with well-defined pre– and postzygapophyses. The posterior part of the centrum is abraded, but the vertebra is clearly procoelous. Two small subcentral foramina are present on the ventral face ( Fig. 11F ). The general shape, presence of transverse processes extending posterolaterally, and broad vertebral cotyle are reminiscent of Caudata ( Rage et al. 1993) . In Caudata , the trunk vertebrae are, however, commonly opisthocoelous or amphicoelous and the procoelous condition is rare (see Estes 1981; Rage et al. 1993; Alloul et al. 2018 for examples of procoelous caudates). On the contrary, the procoelous condition is common within Squamata , to which this vertebra could be alternatively referred. Moreover, anterior basapophyses, which are present in many caudate groups ( Estes 1981), are not discernable, and the presence or absence of a notochordal pit, which is usually observed on caudate vertebrae ( Alloul et al. 2018), cannot be inferred because of the abraded condyle. However, the left transverse process (= rib-bearer), although broken, has an expanded head ( Fig. 11C, E, F ), indicating that it may be bilobed as in salamanders, and a ridge extending between the transverse process and the condyle seems to be present, as in Caudata ( Alloul et al. 2018) , but the preservation is too poor to reach a conclusion. Thus, this vertebra is tentively referred to Caudata?, although an assignment to Squamata cannot be excluded.

Figures

FIG. 11. — Vertebra of Caudata indet. from Angeac-Charente: A-F, (ANG M-71) in anterior (A), posterior (B), left lateral (C), right lateral (D), dorsal (E) and ventral (F) views. Scale bar: 2 mm.