A large Quaternary Dasypodidae from the Lagoa Santa, Brazil: considerations on the presence of extant Cingulata during the Pleistocene

The karst region of Lagoa Santa, eastern Brazil, represents one of the most significant Quaternary palaeontological records in South America, preserving a diverse assemblage of extinct and extant vertebrates. This study presents a comprehensive taxonomic, morphological, and taphonomic analysis of Cingulata remains recovered from two cave deposits. The analysed material comprises more than 1,200 specimens, including both skeletal elements and osteoderms. The first assemblage, which is quantitatively dominant, is characterised by dasypodid taxon assigned to Dasypus punctatus, an extinct species previously reported for the region. This attribution is supported by the diagnostic morphology of the osteoderms as well as by the robust dimensions of the appendicular elements. At least two individuals were identified in this assemblage, including one adult and one subadult. In contrast, the second locality yielded a comparatively small number of specimens, consisting primarily of isolated osteoderms attributable to both extinct and extant taxa, including the genera Dasypus, Cabassous, and Euphractus. While some osteoderms are consistent in size with D. punctatus, others correspond to extant species, suggesting the persistence of these lineages since the Late Pleistocene. Taphonomic analyses indicate distinct depositional histories for the two sites. The assemblage from the more abundant locality reflects predominantly in situ accumulation, followed by weathering, fragmentation, and limited sedimentary reworking, with partial preservation of anatomical associations. Conversely, the second assemblage consists mainly of isolated and occasionally polished osteoderms, indicating secondary deposition under moderate-energy conditions. The coexistence of extinct and extant taxa, combined with the ecological plasticity of the identified genera, suggests that Late Pleistocene environments in the Lagoa Santa region were not characterised by extreme climatic conditions. However, paleoenvironmental reconstructions remain constrained by the ecological generalism of the taxa and the potential effects of temporal mixing within the deposits.