The Skeleton of the Manus of Scelidotherium (Xenarthra, Mylodontidae) Specimens from the Pleistocene of the Province of
- PDF / 5,056,150 Bytes
- 23 Pages / 595.276 x 790.866 pts Page_size
- 5 Downloads / 133 Views
ORIGINAL PAPER
The Skeleton of the Manus of Scelidotherium (Xenarthra, Mylodontidae) Specimens from the Pleistocene of the Province of Córdoba, Argentina, and its Systematic Implications Gastón L. Nieto 1,2 & J. Augusto Haro 1,2 & H. Gregory McDonald 3 & Ángel R. Miño-Boilini 2,4 & Adan A. Tauber 1,5 & Jerónimo M. Krapovickas 1,5 & Maximiliano N. Fabianelli 1 & Federico M. Rosas 1 Accepted: 20 September 2020 # Springer Science+Business Media, LLC, part of Springer Nature 2020
Abstract Dental and craniomandibular data have been predominantly used to infer relationships among mylodontid ground sloths. Recent studies indicate the osteology of the manus also provides useful data to test phylogenetic relationships in mylodontine mylodontids. Here we provide new comparative data from the study of the manus of a member of the Scelidotheriinae, Scelidotherium Owen, 1839, based on specimens from the Province of Córdoba that provide information on the variation and systematic relationships of the genus. The Scelidotherium material from the Province of Córdoba in central Argentina presents several morphological differences with material of the genus from northwestern Argentina. The manus of Scelidotherium shares several traits with Catonyx Ameghino, 1891, but not with Valgipes Gervais, 1874. These include: trapezoid with a sharp ridge on the articular surface for metacarpal II; magnum with at least half of articular surface for metacarpal II located on the dorsal half of the medial and distal aspects of the bone; metacarpal II with a notch on the axial border of its distal articular surface; and ungual process of the distal phalanx of the second digit markedly dorsopalmarly flattened. A phylogenetic analysis that includes osteological characters of the manus indicates that within the family Scelidotheriinae, Scelidotherium is more closely related to Catonyx than to Valgipes or Proscelidodon gracillimus Rovereto, 1914. Keywords Scelidotherium . Manus . Phylogeny . Province of Córdoba
Introduction The osteology of the South American sloth genus Scelidotherium Owen, 1839, is well known (e.g., Owen 1839, 1857; Burmeister 1881; Cuenca Anaya 1995), largely on the basis of very complete individuals belonging to the type
species Scelidotherium leptocephalum Owen, 1839 (Burmeister 1881; Lydekker 1894; Cuenca Anaya 1995). The only other species undoubtedly assigned to this genus, Scelidotherium parodii Kraglievich, 1923, is known by less material, mostly restricted to the skull and humerus (Kraglievich 1923; McDonald 1987; Miño-Boilini 2012).
Electronic supplementary material The online version of this article (https://doi.org/10.1007/s10914-020-09520-x) contains supplementary material, which is available to authorized users. * J. Augusto Haro [email protected] 1
Departamento de Geología Básica, Facultad de Ciencias Exactas, Físicas y Naturales, Universidad Nacional de Córdoba, Vélez Sarsfield 1611, X5016GCA Córdoba, Province of Córdoba, Argentina
2
Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Godo
Data Loading...
