Complex multicusped postcanine teeth from the Lower Triassic of South Africa

Two incisors and five postcanine teeth of complex crown morphology were found in the lower levels of the Burgersdorp Formation of the Beaufort Group, corresponding to the basal Subzone A of the Cynognathus Assemblage Zone (late Olenekian). All the teeth bear a single root and the postcanines show tw...

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Detalles Bibliográficos
Publicado: 2012
Materias:
fossil assemblage
morphology
phylogenetics
tooth
Triassic
Beaufort
North Carolina
South Africa
United States
Cynognathus
Haramiyidae
Mammalia
Therapsida
Acceso en línea:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_02724634_v32_n6_p1411_Gaetano
http://hdl.handle.net/20.500.12110/paper_02724634_v32_n6_p1411_Gaetano
Aporte de:
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) de Universidad de Buenos Aires
id paper:paper_02724634_v32_n6_p1411_Gaetano
record_format dspace
spelling paper:paper_02724634_v32_n6_p1411_Gaetano2023-06-08T15:25:13Z Complex multicusped postcanine teeth from the Lower Triassic of South Africa fossil assemblage morphology phylogenetics tooth Triassic Beaufort North Carolina South Africa United States Cynognathus Haramiyidae Mammalia Therapsida Two incisors and five postcanine teeth of complex crown morphology were found in the lower levels of the Burgersdorp Formation of the Beaufort Group, corresponding to the basal Subzone A of the Cynognathus Assemblage Zone (late Olenekian). All the teeth bear a single root and the postcanines show two rows of mesiodistally aligned cusps and a central basin or groove. Among the postcanines, two general patterns of crown morphology are recognized on the basis of relative length of the cusp rows, number of cusps per row, and width of the central area. Phylogenetic affinities of the described specimens remain unclear, and thus they are regarded as Eucynodontia incertae sedis. However, comparisons with non-mammalian cynodonts with labiolingually expanded postcanines show that they are most similar to those of Aleodon, Candelariodon, and some haramiyids. Many cynodont taxa such as Aleodon, Candelariodon, Cromptodon, haramiyids, and tritylodontids, which are probably not closely related to each other, have labiolingually expanded postcanines with cusps arranged mesiodistally in rows and a central basin; thus pointing to the homoplastic nature of dental morphologies in the cynodont lineage. The teeth presented here are the oldest record of therapsid teeth with crowns having parallel rows of cusps, representing a temporal extension of approximately 10 million years for this crown pattern. © 2012 Copyright Taylor and Francis Group, LLC. 2012 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_02724634_v32_n6_p1411_Gaetano http://hdl.handle.net/20.500.12110/paper_02724634_v32_n6_p1411_Gaetano
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic fossil assemblage
morphology
phylogenetics
tooth
Triassic
Beaufort
North Carolina
South Africa
United States
Cynognathus
Haramiyidae
Mammalia
Therapsida
spellingShingle fossil assemblage
morphology
phylogenetics
tooth
Triassic
Beaufort
North Carolina
South Africa
United States
Cynognathus
Haramiyidae
Mammalia
Therapsida
Complex multicusped postcanine teeth from the Lower Triassic of South Africa
topic_facet fossil assemblage
morphology
phylogenetics
tooth
Triassic
Beaufort
North Carolina
South Africa
United States
Cynognathus
Haramiyidae
Mammalia
Therapsida
description Two incisors and five postcanine teeth of complex crown morphology were found in the lower levels of the Burgersdorp Formation of the Beaufort Group, corresponding to the basal Subzone A of the Cynognathus Assemblage Zone (late Olenekian). All the teeth bear a single root and the postcanines show two rows of mesiodistally aligned cusps and a central basin or groove. Among the postcanines, two general patterns of crown morphology are recognized on the basis of relative length of the cusp rows, number of cusps per row, and width of the central area. Phylogenetic affinities of the described specimens remain unclear, and thus they are regarded as Eucynodontia incertae sedis. However, comparisons with non-mammalian cynodonts with labiolingually expanded postcanines show that they are most similar to those of Aleodon, Candelariodon, and some haramiyids. Many cynodont taxa such as Aleodon, Candelariodon, Cromptodon, haramiyids, and tritylodontids, which are probably not closely related to each other, have labiolingually expanded postcanines with cusps arranged mesiodistally in rows and a central basin; thus pointing to the homoplastic nature of dental morphologies in the cynodont lineage. The teeth presented here are the oldest record of therapsid teeth with crowns having parallel rows of cusps, representing a temporal extension of approximately 10 million years for this crown pattern. © 2012 Copyright Taylor and Francis Group, LLC.
title Complex multicusped postcanine teeth from the Lower Triassic of South Africa
title_short Complex multicusped postcanine teeth from the Lower Triassic of South Africa
title_full Complex multicusped postcanine teeth from the Lower Triassic of South Africa
title_fullStr Complex multicusped postcanine teeth from the Lower Triassic of South Africa
title_full_unstemmed Complex multicusped postcanine teeth from the Lower Triassic of South Africa
title_sort complex multicusped postcanine teeth from the lower triassic of south africa
publishDate 2012
url https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_02724634_v32_n6_p1411_Gaetano
http://hdl.handle.net/20.500.12110/paper_02724634_v32_n6_p1411_Gaetano
_version_ 1768545830757728256

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