Pseudeumeces Hoffstetter, 1944

Vianey-Liaud, Monique, Comte, Bernard, Marandat, Bernard, Peigné, Stéphane, Rage, Jean-Claude & Sudre, Jean, 2014, A new early Late Oligocene (MP 26) continental vertebrate fauna from Saint-Privat-des-Vieux (Alès Basin, Gard, Southern France), Geodiversitas 36 (4), pp. 565-622 : 572

cf. Pseudeumeces Hoffstetter, 1944

( Fig. 1F )

TYPE SPECIES. — Pseudeumeces cadurcensis ( Filhol, 1877) .

MATERIAL EXAMINED. — One anterior part of dentary ( SPV 706).

DESCRIPTION

Ŋe dentary is deep and its subdental shelf (sensu Rage & Augé 2010) markedly thickens anteriorly. Teeth are pleurodont; the most anterior ones are not enlarged but the last tooth of the preserved row is amblyodont, i.e. it is larger than normal teeth. Ŋe enlargement, from the most anterior to the more posterior teeth is progressive. Ŋe apices are round and devoid of cuspids. Striae are present on the apices but they are weak on the largest tooth.

DISCUSSION

Several lizard taxa with amblyodont teeth, or showing tendency toward amblyodonty, are known in the European Cenozoic, mainly from the Oligocene ( Rage 1987, Augé 2005).Ŋe amblyodont condition is weak in Mediolacerta roceki Augé, 2005 (MP 23-MP 30) and is very prominent in Dracaenosaurus croizeti Gervais, 1848 -52 (MP28-MP 30). Morphologically, between these two species occur the intermediate taxa Amblyolacerta Roček, 1884 and Ligerosaurus Augé, Bailon & Malfay, 2003 from the Miocene and Pseudeumeces from the Oligocene. Ŋe fossil from Saint-Privat-des-Vieux may be distinguished from Amblyolacerta and Mediolacerta Augé, 2005 by its stronger amblyodonty. It differs from Ligerosaurus in having a subdental shelf that grows clearly thinner posteriorly and a facet for contact with the splenial that does not reach the anterior part of the bone. In contrast, the fossil does not show any difference with Pseudeumeces and only the incomplete nature of the specimen prevents confident referral to this genus. Pseudeumeces includes a single species, P. cadurcensis ( Filhol, 1877) , that is known from MP 25 to MP 28. Apparently, amblyodont lizards fed at least partly on shelled mollusks (gastropods).

Figures

FIG. 1. — Amphibians and lizards from Saint-Privat-des-Vieux (Gard; Lower Chattian,MP 26): A-C, Discoglossus Otth, 1837 or Latonia Meyer, 1843: A, left ilium (SPV701) in lateral view; B, right scapula (SPV702) in lateral view; C, right angulare (SPV715) in dorsal view; D, E, Pelophylax sp.: D, right humerus (SPV705) in ventral view; E, left ilium (SPV704) in lateral view; F, cf. Pseudeumeces Hoffstetter, 1944, left dentary (SPV706) in medial view; G, H,?Shinisauria indet., right maxilla (SPV709): G, lateral view; H, medial view; I, am- phisbaenian A, left dentary (SPV707) in medial view; J, amphisbaenian B, right dentary (SPV708) in medial view. Scale bars: 3 mm.