On the fossil Remains of Panochthus Burmeister, 1866 (Xenarthra, Cingulata, Glyptodontidae) from the Pleistocene of southern Brazil

Abstract

The genus Panochthus represents the last lineage of "Panochthini" recorded in the Pleistocene. This genus has a wide latitudinal distribution in South America, and in Brazil it occurs in the southern and northeastern regions. In this paper we describe new material (isolated osteoderms and caudal tube fragments) assigned to Panochthus from the state of Rio Grande do Sul (southern Brazil) and discuss some taxonomic issues related to Panochthus tuberculatus and Panochthus greslebini based on this material . The occurrence of P. greslebini is the first for outside the Brazilian Intertropical Region. In addition, we describe new diagnostic features to differentiate the osteoderms of P. greslebini and P. tuberculatus. Unfortunately, it was not possible to identify some osteoderms at the species level. Interestingly, they showed four distinct morphotypes characterized by their external morphology, and thus were attributed to Panochthus sp. Lastly, we conclude that in addition to P.tuberculatus registered to southern Brazil, there is another species of the genus, assignable to P. cf. P. greslebini. Our analysis reinforce the reliability of caudal tube characters for the classification of species of Panochthus.

New exoskeletal material from Bahia provides new evidence of geographic distribution and paleopathology for Quaternary cingulates

“…The distribution of the genus Panochthus encompasses Argentina, Bolivia, Brazil, Paraguay, and Uruguay (Ferreira et al, 2015). For Brazil, the species Panochthus tuberculatus are recorded for the southern region (Ribeiro & Scherer, 2009), and Panochthus greslebini and Panochthus jaguaribensis for the Northeast (Porpino & Bergqvist, 2002;Ribeiro & Carvalho, 2009;Porpino et al, 2014).…”

The paleoecology of Pleistocene giant megatheriid sloths: stable isotopes (δ13C, δ18O) of co-occurring Megatherium and Eremotherium from southern Brazil

“…Considering the co-occurrence of Brazilian and Pampean fossils in the Chuí Creek local fauna (Lopes et al, 2021), this Atlantic corridor allowed other elements of the intertropical megafauna such as the canid Protocyon troglodytes (Oliveira et al, 2005) and the glyptodont Panochthus greslebini (Ferreira et al, 2015) to reach the CPRS, following southward expansion of tropical environments during warm (interglacial/ interstadial) stages. On the other hand, some Pampean taxa found in the CPRS such as Megatherium and the glyptodont Doedicurus clavicaudatus (Pereira et al, 2012), which is absent in northeastern Argentina (Francia et al, 2015), may have also migrated northward along this route, possibly during glacial epochs, when sea-levels lower than the present one exposed most of the continental shelf, as indicated by the abundance of mammalian fossils on the inner shelf off Rio Grande do Sul (Lopes & Buchmann, 2010;Aires & Lopes, 2012;Lopes & Pereira, 2019).…”