Theriosuchus sp.

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 : 704

Theriosuchus sp.

( Fig. 17 A-D)

DESCRIPTION

Small isolated teeth are commonly recovered from residues obtained from bulk screening. Many of them ( Fig. 17 A-D) are leaf-shaped, labiolingually compressed, low-crowned and pseudoziphodont, a characteristic of the posterior dentition in the atoposaurid genus Theriosuchus ( Schwarz & Salisbury 2005; Lauprasert et al. 2011; Martin et al. 2014b). Members of the genus Theriosuchus are small crocodyliforms with total body lengths less than 1m ( Schwarz & Salisbury 2005). Besides teeth, two skull bones might belong to this genus: a right jugal (ANG 16-5179) and a fragmentary frontal (ANG 14-3692). The jugal is about 1 cm long and its ornamented lateral surface is thin and projects ventrally. The frontal preserves the interorbital area and displays an acute median keel on its dorsal surface. A finely sculpted osteoderm, longer than wide and possessing a shallow median keel ( Fig.19D ), matches the morphology of dorsal osteoderms of the tail region in Theriosuchus pusillus ( Owen 1879; Clark 1986).

Figures

FIG. 17. — Crocodyliform teeth from Angeac-Charente: A-D, broadened teeth of Theriosuchus sp., ANG M-13 (A), ANG M-07 (B), ANG M-19 (C), ANG M-12 (D); E, tooth of Bernissartiidae indet. (ANG M-11). Scale bar: 1 mm.

FIG. 19. — Crocodyliform remains from Angeac-Charente: A, B, tooth of Bernissartiidae indet. (ANG10-268) in lingual/labial (A) and occlusal (B) views;C, tooth of Bernissartiidae indet. (ANG10-76) in lingual/labial view; D, osteoderm of Atoposauridae? (ANG 10-167) in dorsal view; E, F, tooth of Pholidosaurus sp. (ANG11- 960) in labial (E) and mesial/distal (F) views; G, H, tooth of Pholidosaurus sp. (ANG11-883) in labial (G) and mesial/distal (H) views I, J, tooth of Pholidosaurus sp. (ANG10-369) in labial (I) and mesial/distal (J) views. Scale bar represents: A-C, 2 mm; D-J, 8 mm.