A new early-diverging probainognathian cynodont and a revision of the occurrence of cf. Aleodon from the Chañares Formation, northwestern Argentina : New clues on the faunistic composition of the latest Middle-?earliest Late Triassic Tarjadia Assemblage Zone

© 2024 American Association for Anatomy..

The Chañares Formation (Ischigualasto-Villa Unión Basin) is worldwide known by its exquisitely preserved fossil record of latest Middle-to-early Late Triassic tetrapods, including erpetosuchids, "rauisuchians," proterochampsids, gracilisuchids, dinosauromorphs, pterosauromorphs, kannemeyeriiform dicynodonts, and traversodontid, chiniquodontid and probainognathid cynodonts, coming from the Tarjadia (bottom) and Massetognathus-Chanaresuchus (top) Assemblage Zones of its lower member. Regarding cynodonts, most of its profuse knowledge comes from the traditional layers discovered by Alfred Romer and his team in the 1960s that are now enclosed in the Massetognathus-Chanaresuchus Assemblage Zone (AZ). In this contribution we focus our study on the probainognathian cynodonts discovered in levels of the Tarjadia Assemblage Zone. We describe a new chiniquodontid cynodont with transversely broad postcanine teeth (Riojanodon nenoi gen. et sp. nov.) which is related to the genus Aleodon. In addition, the specimen CRILAR-Pv 567 previously referred to cf. Aleodon is here described, compared, and included in a phylogenetic analysis. It is considered as an indeterminate Aleodontinae nov., a clade here proposed to included chiniquodontids with transversely broad upper and lower postcanines, by having a cuspidated sectorial labial margin and a lingual platform that is twice broader than a lingual cingulum. Cromptodon mamiferoides, from the Cerro de Las Cabras Formation (Cuyo Basin), was also included in the phylogenetic analysis and recovered as an Aleodontinae. The new cynodont and the record of Aleodontinae indet. reinforce the faunal differentiation between the Tarjadia and Massetognathus-Chanaresuchus Assemblage Zones, in the lower member of the Chañares Formation, and inform on the diverse chiniquodontid clade with both sectorial and transversely broad postcanine teeth.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:307

Enthalten in:

Anatomical record (Hoboken, N.J. : 2007) - 307(2024), 4 vom: 15. März, Seite 818-850

Sprache:

Englisch

Beteiligte Personen:

Martinelli, Agustín G [VerfasserIn]
Ezcurra, Martín D [VerfasserIn]
Fiorelli, Lucas E [VerfasserIn]
Escobar, Juan [VerfasserIn]
Hechenleitner, E Martín [VerfasserIn]
von Baczko, M Belén [VerfasserIn]
Taborda, Jeremías R A [VerfasserIn]
Desojo, Julia B [VerfasserIn]

Links:

Volltext

Themen:

Chiniquodontidae
Cynodontia
Journal Article
Probainognathia
South America
Taxonomy

Anmerkungen:

Date Completed 18.03.2024

Date Revised 18.03.2024

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1002/ar.25388

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM367729288