The objective of the present work is to compare the presence of Pleistocene vertebrate fossils from the central and southern sectors of the Coastal Plain of Rio Grande do Sul, quantifying and qualifying the taphonomy, and taxonomic group and skeletal remains representativeness. A total of 2,820 fossils was collected, among them 95% were collected in the southern sector and 5% in the central sector. In both sectors were identified two populations of bioclasts: non-identified fossils (85%) and identified fossils (15%). The same taxonomic groups and skeletal remains were identified in both sectors, except for some due to the different amount of fossils collected. The two populations of bioclasts identified represent greater (85% non-identified) or less (15% identified) reworking by waves. The hypothesis for the different amount of fossils collected is the availability of fossils on the shoreface and inner continental shelf. The presence of several submerged sedimentary rocks and records of paleolagoons and paleochannels on the shoreface and inner continental shelf of the southern sector indicates probably the source-areas where the skeletal remains were once fossilized and now are being eroded.

-EVIDENCE OF GREGARIOUS BEHAVIOUR IN PALEOBURROWS OF MYLONDONTIDAE (GIANT SLOTHS). This article presents evidence of gregarious behavior in paleoburrows attributed to giant sloths. Paleoburrows are biogenic structures in the shape of galleries and halls excavated by extinct giant mammals that lived in the Pliocene and Pleistocene. In the case discussed here, they were excavated in rocks composed by neoproterozoic metadiamictites with hematite of the Macaúbas Group (Nova Aurora Formation). The rocks, of glacial origin, underwent metamorphism, were strongly cemented by hematite and exhibit high hardness. In the north of Minas Gerais, were identified new paleoburrows distributed in a grouped manner, located in valleys with steep slopes embedded in geological faults. In each group, the paleoburrows are arranged on both sides of the valley, facing at each other. At the walls and roofs of the paleoburrows, there are hundreds of claw marks, forming parallel double marks and intertwined marks. Silicone molds of the marks were compared with hand bones of Valgipes sp. (Mylodontidae) deposited in the collection of PUC-MG; the size and morphology of the double marks allowed to attribute these paleoburrows to digging mylodontids (two-toed giant sloths). At the lateral walls of the paleoburrows we identified several polished surfaces of elliptical shape, each one with a diameter of approximately 2.4 m. These polished surfaces aroused due to the abrasive action of the giant sloths´ fur at their resting place. A single paleoburrow may show from 1 to 3 of these elliptical surfaces, suggesting a gregarious behavior of the sloths, who slept together in these spaces.Key words: megafauna, Quaternary, Minas Gerais, ichnofossils.RESUMO -Este estudo apresenta evidências de vida gregária em paleotocas atribuídas às preguiças-gigantes. As paleotocas são estruturas biogênicas na forma de galerias e salões escavados por mamíferos gigantes extintos que viveram no Plioceno e Pleistoceno. Foram escavadas em rochas compostas por metadiamictitos hematíticos neoproterozoicos do Grupo Macaúbas (Formação Nova Aurora). As rochas de origem glacial sofreram metamorfismo, são fortemente cimentadas por hematita, e apresentam elevada dureza. No norte de Minas Gerais foram identificadas novas paleotocas distribuídas de forma agrupada, em vales de encostas íngremes encaixados em falhas. Em cada agrupamento as paleotocas estão dispostas nos dois lados dos vales, umas em frente às outras. Nas paredes e no teto das paleotocas há centenas de marcas de garras, formando marcas duplas paralelas e marcas entrelaçadas. Moldes em silicone das marcas foram comparados com ossos das mãos de Valgipes sp. (Mylodontidae) depositados na coleção da PUC-MG; o tamanho e morfologia das marcas duplas permitem atribuir estas paleotocas a milodontídeos cavadores (preguiças-gigantes de dois dedos). Nas paleotocas foram identificadas diversas superfícies polidas de formato elíptico, com cerca de 2,4 m de diâmetro, atribuídas ao desgaste da rocha devido ao atrito da pelage...