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A new species of water vole from the Early Pleistocene of Southern Europe

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Cuenca-Bescos G., Agusti J., Lira J., Melero-Rubio M., Rofes J.

Acta Palaeontologica Polonica

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2010

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tom 55

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nr 4

In the Early Pleistocene Red Lower Unit of the Sima del Elefante site (Sierra de Atapuerca karst complex, Burgos, Spain), levels TE9–TE13, dental and mandibular remains of an arvicoline are referred to as the new species Arvicola jacobaeus sp. nov. The new species has medium−sized hypselodont molars, with abundant cementum in the re−entrant folds, and thick enamel band with differentiation of the Mimomys−type. The occlusal morphology of M3 is simple. The dental morphology of the new species resembles that of Arvicola sapidus, though smaller. It is more derived, in size and morphology than the Middle Pleistocene species Arvicola mosbachensis. The morphologic affinities among Arvicola jacobaeus, Arvicola terrestris, and A. sapidus suggest a common ancestry. A preliminary phylogenetic analysis corroborates that Mimomys savini is the sister group of the Arvicola clade.

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Postcranial skeleton of a Cretaceous multituberculate mammal Catopsbaatar

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Hurum J. H., Kielan-Jaworowska Z.

Acta Palaeontologica Polonica

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2008

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tom 53

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nr 4

We describe an incomplete postcranial skeleton of Catopsbaatar catopsaloides from the ?late Campanian red beds of Hermiin Tsav I, in the Gobi Desert, Mongolia. The skeleton is fragmentary and the preservation of bone surface does not permit reconstruction of the musculature. The studied skeleton contains some parts not preserved or incompletely known in other multituberculate genera, such as a long spinous process in a single lumbar vertebra, which together with long transverse processes preserved in Nemegtbaatar, might indicate that at least some multituberculates had jumping ability. The calcaneus of Catopsbaatar is unusual, differing from most other multituberculates (where known) and other mammals by having a short tuber calcanei, with a large proximal anvil−shaped process strongly bent laterally and ventrally, arranged obliquely with respect to the distal margin of the calcaneus, rather than arranged at 90° to it, as in other mammals. This suggests the presence of strong muscles that attached to the tuber calcanei, perhaps further attesting to jumping abilities in Catopsbaatar. We also describe an unfused pelvic girdle and the first extratarsal spur bone (os cornu calcaris) known in multituberculates.

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A taxonomic and biogeographic review of the fossil tapirs from Bolivia

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Ferrero B. S., Soibelzon E., Holanda E. C., Gasparini G. M., Zurita A. E., Mino-Boilini A. R.

Acta Palaeontologica Polonica

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2014

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tom 59

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nr 3

Fossil remains of South American tapirs are often fragmentary and scarce compared with those of other mammals that entered South America during the “Great American Biotic Interchange”. Here, we review and add to the Pleistocene tapir remains from the Tarija Valley (Bolivia), and provide a taxonomic re-evaluation of Tapirus tarijensis. T. tarijensis was a large-sized animal, approximating the size of the living Malaysian T. indicus and the extinct North American T. haysii. The geographical distribution of Pleistocene records of Tapirus in South America indicates that T. tarijensis was the only known species inhabiting the Tarija Valley during this time.

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Late Miocene capybaras from Argentina: Skull anatomy, taxonomy, evolution, and biochronology

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Vucetich M. G., Deschamps C. M., Vieytes E. C., Montalvo C. I.

Acta Palaeontologica Polonica

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2014

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tom 59

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nr 3

Fossil capybaras are morphologically extremely varied, but previous studies have disagreed on whether this diversity reflects intraspecific variation or the existence of multiple species. Here, we review the capybaras from the classic Argentinian Late Miocene localities of Paraná River cliffs (“conglomerado osífero” of the Ituzaingó Formation, Entre Ríos), and Chillhué and Guatraché shallow lakes (Cerro Azul Formation, La Pampa), and perform a morphometric analysis of their upper cheek teeth and the posterior portion of the rostrum. Our results confirm that all of the specimens from the “conglomerado osífero” belong to the single species Cardiatherium paranense. In addition, we refer a specimen from Tupungato (Río de los Pozos Formation, Mendoza) to C. paranense, thus expanding its geographical range. The material from La Pampa represents a different taxon, and is here preliminary referred to Cardiatherium aff. orientalis. Our systematic interpretation of Late Miocene capybaras suggests that the early radiation of this group was not as explosive as previously thought, and was likely constrained by the early acquisition of large size, increasing complexity of the cheek teeth, and probably semi-aquatic habits.

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Osteoderm histology of Late Pleistocene cingulates from the intertropical region of Brazil

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Da Costa Pereira P. V. L. G., Victer G. D., Porpino K. O., Bergqvist L. P.

Acta Palaeontologica Polonica

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2014

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tom 59

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nr 3

During the Late Pleistocene, several possibly endemic cingulate species, known mostly from isolated osteoderms, carapace fragments, and caudal tubes, coexisted in the Brazilian Intertropical Region. Here, we describe the osteoderm microstructure of Pachyarmatherium brasiliense, as well as the glyptodonts Panochthus greslebini, Panochthus jaguaribensis and Glyptotherium sp., in order to provide additional species-diagnostic characters and shed light on their evolutionary relationships. Pachyarmatherium brasiliense lacks several derived features shared by glyptodonts and pampatheres, such as extensive bone remodeling, fibers arranged in large bundles, and relatively poorly developed layers of compact bone, thus supporting its exclusion from glyptodonts as suggested by a recent cladistic study. The osteoderm histology of P. greslebini resembles that of other species of Panochthus (e.g., Panochthus frenzelianus). By contrast, the presence of relatively thick layers of compact bone, the configuration and size of resorption areas, the absence of randomly oriented lateral fiber bundles, and the absence of an intermediary region between the compact and trabecular bone potentially support the exclusion of Panochthus jaguaribensis from the genus. Finally, osteoderms of the Brazilian specimens of Glyptodontinae share histological features with Glyptotherium floridanus, rather than Glyptodon, thus reinforcing their assignment to Glyptotherium. These results highlight the relevance of histological osteoderm characters in cingulate systematics, ands call for further and more comprehensive studies.

Ograniczanie wyników

5 Acta Palaeontologica Polonica

1 Agusti J.

1 Bergqvist L. P.

1 Cuenca-Bescos G.

1 Da Costa Pereira P. V. L. G.

1 Deschamps C. M.

1 Ferrero B. S.

1 Gasparini G. M.

1 Holanda E. C.

1 Hurum J. H.

1 Kielan-Jaworowska Z.

1 Lira J.

1 Melero-Rubio M.

1 Mino-Boilini A. R.

1 Montalvo C. I.

1 Porpino K. O.

1 Rofes J.

1 Soibelzon E.

1 Victer G. D.

1 Vieytes E. C.

1 Vucetich M. G.

1 Zurita A. E.

3 2014

1 2010

1 2008

A new species of water vole from the Early Pleistocene of Southern Europe

Postcranial skeleton of a Cretaceous multituberculate mammal Catopsbaatar

A taxonomic and biogeographic review of the fossil tapirs from Bolivia

Late Miocene capybaras from Argentina: Skull anatomy, taxonomy, evolution, and biochronology

Osteoderm histology of Late Pleistocene cingulates from the intertropical region of Brazil