Representativity of Quaternary mammals from the Southern Brazilian continental shelf

Abstract

Fossils of terrestrial mammals from the southern Brazilian continental shelf have been known since the late 19th century. The fossils are relatively common and represent several taxonomic groups of the Pleistocene megafauna. Although the systematics of the fossil assemblage is well known, the relative proportions among taxonomic groups and their skeletal elements have not been evaluated yet. Here are presented the results of a survey of the diversity of skeletal elements and taxa among 2,391 specimens belonging to the paleontological collection of the Universidade Federal do Rio Grande (FURG). The survey revealed that the most common taxa are the artiodactyls, ground sloths, glyptodontids and toxodontids, while carnivores, rodents and litopterns are very scarce. The most abundant skeletal elements are osteoderms of cingulates (mostly glyptodontids) and teeth of other groups. Although paleoecological and paleoenvironmental inferences are very hard to obtain because the fossils do not have a stratigraphic setting, encompass a wide time span, of some 700 ky BP, and represent several environments and climates, some patterns of taxonomic abundance are apparently related to ecological factors, while others seem to result from taphonomic processess.

On the presence of Megatherium Cuvier, 1796 (Xenarthra, Pilosa) in fossiliferous deposits of the Coastal Plain of Southern Brazil

“…The dubious specific assignment of the dentary MCTFM-PF0778 results of the loss of its posterior and anterior ends and the small size which suggests that it could be a sub-adult individual of either M. americanum or M. gallardoi, based on the similar MBH/ MTRL with the latter. Although the latter species is known so far from the Ensenadan deposits of Argentina (Brandoni et al, 2008), the hypothesis of its presence in the CPRS cannot be discarded, given the faunal similarity between the paleomastofauna of the two areas and the biostratigraphic correlation of some fossils from the continental shelf, such as Neolicaphrium and Panochthus subintermedius Aires & Lopes, 2012;Ferreira et al, 2015), with units older than the Bonaeran of Argentina. However, more specimens with unambiguous morphological features are necessary in order to assess this hypothesis.…”

“…Today, those deposits are being eroded by storm waves that transport the fossils to the shore, thus forming large Konzentrat-Lagerstätten on the beach (Figueiredo, 1975;. These concentrations include remains of both marine and terrestrial organisms, the latter represented by animals that inhabited the continental shelf during periods when it was subaerially exposed due to sea-level lowstands Aires & Lopes, 2012).…”

Post mortem modifications (pseudopaleopathologies) in middle-late Pleistocene mammal fossils from southern Brazil

“…All fossils are disarticulated; the most abundant skeletal elements belong to Voorhies' group I (192 specimens), followed by 30 that belong to group II, 28 to group III and 5 that could not be assigned to any of these groups (Table 2); 121 specimens are complete, 86 incomplete and 48 are fragments. These relative proportions are somewhat biased because fossil collecting is aimed at well-preserved or identifi able specimens; direct observation indicate that the total amount of small, unidentifi able fragments in the Concheiros is much larger than this (Lopes & Buchmann, 2010;Aires & Lopes, 2012).…”

First record of the Neolicaphrium recens Frenguelli, 1921 (Mammalia, Litopterna) in the Pleistocene of Santiago del Estero Province, Argentina

“…Remains of proterotheriids have been found mainly in Argentina, but also in Colombia, Peru, Bolivia (Soria, 2001), Venezuela (Linares, 2004), Brazil (Cifelli, 1983;Scherer et al, 2009;Aires & Lopes, 2012) and Uruguay (Ubilla et al, 2004(Ubilla et al, , 2011. After the late Miocene this group becomes severely reduced in diversity and frequency and the family survives until the Pleistocene with a single genus, Neolicaphrium Frenguelli, 1921. Two species of Neolicaphrium are recognized: N. recens Frenguelli, 1921 andN.…”