Contribuições à sistemática do gênero Artibeus Leach, 1821 (Chiroptera, Phyllostomidae) com base em dados morfológicos e moleculares: implicações para evolução e conservação

Abstract

The genus Artibeus has been the subject of extensive debate regarding its systematics, which remains complex and controversial, primarily due to insufficient information and significant variation across different taxa within the group. This study integrates two complementary approaches to investigate the taxonomy, systematics, and population dynamics of Artibeus in Brazil. The first part of the research employs an integrative analysis using morphological, molecular, and geometric morphometric data to elucidate intra- and interspecific relationships among species of the genus. In this study, we generated two datasets: one based on molecular species delimitation using the barcode region (COI) and another incorporating cranial size and shape data analyzed through Geometric Morphometrics (GM) methods. The species delimitation results identified molecular operational taxonomic units (MOTUs) that align with the morphological identification of the species. GM analyses revealed significant inter- and intraspecific variation in cranial size and shape among Artibeus species. The combined results suggest a lack of a strong phylogenetic signal driving skull variation. This finding indicates that historical ecological factors may have played a key role in shaping cranial morphology, acting as selective pressures across geographic space and contributing to intraspecific variation in Artibeus planirostris. The second part of the study investigated the population genetic structure of A. planirostris using mitochondrial markers with extensive sampling. Our findings reveal substantial genetic differentiation among populations, with limited gene flow, particularly in peripheral regions compared to northern South America. This suggests that local adaptations, shaped by specific environmental pressures and Pleistocene climatic fluctuations, may have influenced the dispersal and colonization capacity of A. planirostris in these areas. These findings support the hypothesis that isolation by distance may also contribute to the observed distribution pattern. The demographic history of A. planirostris indicates a recent population expansion during the Late Pleistocene, approximately 50,000 to 60,000 years ago.