NEW TRAVERSODONTID CYNODONT FROM THE LATE TRIASSIC CHAÑARES FORMATION
Nuevo cinodonte traversodóntido del Triásico Tardío de la Formación Chañares
DOI:
https://doi.org/10.5710/PEAPA.01.08.2025.540Keywords:
Anatomy, Cynodontia, Traversodontid, Gondwana, Late Triassic, CarnianAbstract
The Chañares Formation in north-western Argentina has provided an impressive number of specimens of early archosauriforms, dicynodonts, and non-mammaliamorph cynodonts. However, there is a very low diversity of cynognathian cynodonts. Herein, we report on Pontognathus ignotus gen. et sp. nov., a small new traversodontid from the traditional Late Triassic Carnian levels of the unit. It differs from other traversodontids for lacking a maxillary platform lateral to the posterior postcanines and by presenting a unique combination of characters from the premaxilla, maxilla, and dentition (i.e., the precanine diastema; the placement of the paracanine fossa; the number of upper postcanines; the general outline of the upper postcanines crown in occlusal view; the shouldering between adjacent teeth; the expansion of the crown distolateral to the sectorial crest; the extension, limits and deepness of the occlusal basin; the distal ridge-like bulging at the base of the crown; the number and relative placement and development of the cusps). It is a relatively small taxon inferred to have occupied a specialized, small herbivorous/omnivorous role, which in this fauna is otherwise only shared by small individuals of the traversodontid Massetognathus pascuali.
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0.443 Q2 | H Index 11
CiteScore 1.7
