Argentoconodon, ROUGIER & GARRIDO & GAETANO & PUERTA & CORBITT & NOVACEK, 2007

ROUGIER, GUILLERMO W., GARRIDO, ALBERTO, GAETANO, LEANDRO, PUERTA, PABLO F., CORBITT, CYNTHIA & NOVACEK, MICHAEL J., 2007, First Jurassic Triconodont from South America, American Museum Novitates 3580, pp. 1-20 : 4-6

Argentoconodon , new genus figures 3 , 4

TYPE AND ONLY SPECIES: Argentoconodon fariasorum , new species .

ETYMOLOGY: Argento, from Argentina, the country were the holotype was found; and con odon, from the Greek ‘‘conical tooth’’, in reference to the conical aspect of the cusp of the first described triconodonts, and now a common ending of triconodont names. The species name fariasorum is from Farias, after Ricardo Farias and his family, who have supported paleontological research on their land for decades. They have been gracious hosts who greatly facilitated our work. Our knowledge of the continental Jurassic in Argentina owes much to their longstanding support.

DIAGNOSIS: Generic and specific diagnoses are the same because only one species is known. ‘‘Amphilestid’’ with a pentacuspid lower molar consistent of three main cusps b, a, c and small anterior and posterior cusps. All cusps are recurved to some degree and a small accessory cusp is present lingual to the notch between cusps a and c in the position of g (Kuehneocone of morganucodonts). Cusps b and c are subequal in height. Accessory cusps e and d extend mesially and distally (respectively) from the crown base. Interdental contact is in echelon. The crown is extremely compressed buccolingually.

PROVENANCE: The holotype is housed in the Museo Paleontólogico ‘‘Egidio Feruglio’’ (MPEF) in Trelew (Province of Chubut), Argentina, and bears the collection number MEF-PV 1877. The specimen was collected in March 2003 at the local school in Cerro Cóndor by breaking assorted blocks from the Queso Rallado locality (43 ° 24 9 33.55 0 S, 69 ° 13 9 50.1 0 W), about 5.5 km west-northwest of the village of Cerro Cóndor ( Bonaparte, 1979, 1986b; Rauhut et al., 2002; Martin and Rauhut, 2005), in Chubut Province, Argentina.

ASSOCIATED FAUNA: Vertebrates at the Queso Rallado locality mainly occur as isolated elements of small to mid-sized animals; articulated or associated remains are present, although scarce. The vertebrate fauna of the Queso Rallado seem to represent a composite of aquatic and terrestrial animals in agreement with littoral lacustrine sedimentary conditions inferred from the fossil-bearing strata at Queso Rallado. Small aquatic basal turtles, anurans, and crocodiles dominate numerically; fish elements and other aquatic vertebrates are far more scarce. Terrestrial vertebrate elements are relatively rare and are represented by sphenodontians, pterosaurs, dinosaurs (teeth), and mammals.

Figures

Fig. 3. Stereophotographs of Argentocondon fariasorum (MPEF PV 1877) in labial (A) and lingual (B) views.

Fig. 4. Illustrations of Argentoconodon fariasorum (MPEF PV 1877) in lingual (A), labial (B), occlusal