Pachycynodon crassirostris Schlosser, 1888

Bonis, Louis de, Gardin, Axelle & Blondel, Cécile, 2019, Carnivora from the early Oligocene of the ‘ Phosphorites du Quercy’ in southwestern France, Geodiversitas 41 (15), pp. 601-621 : 604-606

Pachycynodon crassirostris Schlosser, 1888

TYPE SPECIMEN. — Lectotype, right P 4 in Schlosser 1888: 29, pl. IX, fig. 2 and 9 “Phosphorites du Quercy”, BSP 1879XV40, Museum of Munich, by subsequent designation of Peigné et al. 2014.

DESCRIPTION

The type specimen of the species Pachycynodon crassirostris Schlosser, 1888 , an isolated P4 comes from an unknown locality in the Quercy phosphorites, without any biostratigraphic indicators. This tooth is not frequent in the collections and, except for P. boriei, never associated with a mandible. The P4 is not a good diagnostic element for a species insofar as all type specimens of other species are mandibles and lower dentitions. Schlosser considered that the type could correspond to a mandible named Cynodictis crassirostris Filhol, 1882 but we don’t know the criteria he used (see above). Later (1899) he figured other specimens from Quercy, a mandible and an m1 ( Schlosser 1899: pl. VIII, figs 1, 8), which seemed to him match the upper tooth considered as the type specimen. Teilhard figured a Quercy mandible from the Museum of Montauban ( Teilhard 1915: pl. IV, fig.11) as P. crassirostris . The latter was synonymised by Cirot (1992) because of mandibular morphology with another Quercy species, Cynodictis dubius Filhol, 1882 ( 1882: pl. VIII, figs 11-13) of which type specimen, a mandible, is housed in the MNHN Paris (no. MNHN.F.QU3231). However an examination of this specimen (by LdeB) shows that it belongs in the genus Pachycynodon but differs from the Montauban mandible by its smaller size, relatively lower cuspids of m1 trigonid, relatively longer m2

and shallower mandibular corpus. Thus, we think that P. dubius is really a different species. Pachycynodon crassirostris was recorded in Valbro (MP 22) by Peigné et al. (2014: fig. 26a) from a worn mandible whose wear is almost horizontal, probably indicating a hypocarnivorous diet ( Peigné et al. 2014: fig. 20), but see below for Pachycynodon amphictina n. stat. Currently, the lower dentition of P. crassirostris is unknown.