Tessellatia

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Tessellatia
Temporal range: Late Triassic
(mid-Norian), 220–211  Ma
Tessellatia Holotype.webp
Holotype cranium of Tessellatia in various views and interpretations
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Synapsida
Clade: Therapsida
Clade: Cynodontia
Clade: Probainognathia
Genus: Tessellatia
Gaetano et al., 2022
Species:
T. bonapartei
Binomial name
Tessellatia bonapartei
Gaetano et al., 2022

Tessellatia is an extinct genus of probainognathian cynodont from the Late Triassic Los Colorados Formation of La Rioja, Argentina. The genus contains a single species, T. bonapartei, known from a partial skull. [1]

Discovery and naming

Layers of the 'La Esquina' locality of the Los Colorados Formation where the holotype was discovered Los Colorados Formation, 'La Esquina' Locality.jpg
Layers of the 'La Esquina' locality of the Los Colorados Formation where the holotype was discovered

The Tessellatia holotype specimen, PULR-V121, was discovered in upper layers of the Los Colorados Formation in Talampaya National Park in La Rioja Province, Argentina. The specimen consists of a partial skull, including the snout and orbital region, and lower jaws. [1]

In 2022, Gaetano et al. described Tessellatia as a new genus and species of probainognathian cynodont. The generic name, "Tessellatia", is derived from the Latin "tessella" (the individual tiles making up a mosaic), in reference to a conglomerate of basal and derived features seen in the taxon. The specific name, "bonapartei", honors the Argentine paleontologist José F. Bonaparte, who described the first cynodont fossils from the Los Colorados Formation. [1]

Related Research Articles

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<i>Probainognathus</i> Extinct genus of cynodonts

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<i>Coloradisaurus</i> Extinct genus of dinosaurs

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<span class="mw-page-title-main">Los Colorados Formation</span>

The Los Colorados Formation is a sedimentary rock formation of the Ischigualasto-Villa Unión Basin, found in the provinces of San Juan and La Rioja in Argentina. The formation dates back to the Norian age of the Late Triassic.

<span class="mw-page-title-main">Ischigualasto Formation</span> Geological formation in Argentina

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<i>Aleodon</i> Extinct genus of cynodonts

Aleodon is an extinct genus of cynodonts that lived from the Middle to the Late Triassic. Relatively few analyses have been conducted to identify the phylogenetic placement of Aleodon, however those that have place Aleodon as a sister taxon to Chiniquodon. Two species of Aleodon are recognized: A. brachyramphus which was discovered in Tanzania, and A. cromptoni which was discovered most recently in Brazil.

<i>Bonacynodon</i> Extinct genus of cynodonts

Bonacynodon is an extinct genus of cynodonts that lived in what is now southern Brazil during the Triassic period. The genus is monotypic, containing only the type species Bonacynodon schultzi. B. schultzi is known from two specimens, consisting of two partial skulls and some badly preserved parts of the postcranium. Both specimens were recovered from the Pinheiros-Chiniquá Sequence, part of the Santa Maria Supersequence of the Paraná Basin. This sequence preserves a faunal association known as the Dinodontosaurus Assemblage Zone, which contains numerous other species of cynodonts, dicynodonts and reptiles. Bonacynodon was a small, likely insectivorous cynodont, whose length has been estimated at around 30 centimetres (12 in). It can be distinguished from other cynodonts by its large, serrated (saw-like) canine teeth. Together with the genus Probainognathus of Argentina, it made up the family Probainognathidae, one of the earliest-diverging lineages of the clade Probainognathia. It was a fairly close relative of mammals, the only group of cynodonts alive today.

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Agudotherium is an extinct genus of probainognathian cynodonts from the Late Triassic Candelária Formation of the Paraná Basin in southern Brazil. The genus contains one species, Agudotherium gassenae. A. gassenae is known from three specimens, all consisting of partial lower jaws.

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<i>Santacruzgnathus</i> Extinct genus of cynodonts

Santacruzgnathus is an extinct genus of small cynodonts from the Late Triassic (Carnian) Santacruzodon Assemblage Zone of Brazil. It contains one species, S. abdalai. Santacruzgnathus is known from a single partial lower jaw with four postcanine teeth, only one of which is well-preserved. Some features of the specimen, including the slender shape of the jaw and the incipiently double-rooted teeth, indicate that the animal was an early member of Prozostrodontia, a group that includes mammals and their close relatives.

References

  1. 1 2 3 Gaetano, L. C.; Abdala, F.; Seoane, F. D.; Tartaglione, A.; Schulz, M.; Otero, A.; Leardi, J. M.; Apaldetti, C.; Krapovickas, V.; Steimbach, E. (2022). "A new cynodont from the Upper Triassic Los Colorados Formation (Argentina, South America) reveals a novel paleobiogeographic context for mammalian ancestors". Scientific Reports. 12 (1): Article number 6451. Bibcode:2022NatSR..12.6451G. doi: 10.1038/s41598-022-10486-4 . PMC   9038739 . PMID   35468982.