Contribuições ao conhecimento biogeográfico de Mesembrinellidae e estudo faunístico de Calliphoridae e Mesembrinellidae (Diptera: Oestroidea) no sul do Brasil

Abstract

Calliphoridae and Mesembrinellidae (Diptera: Oestroidea) are families of calyptrate dipteran. Califorids have a worldwide distribution and are of major importance for forensic entomology and veterinary sciences, since its larvae have saprophagous or ectoparasitic habits. The mesembrinellids have a distribution restricted to the Neotropical region, presenting a potential role to act as bioindicators, since their occurrence is almostly restricted to forest environments. The knowledge of the fauna of these families in Rio Grande do Sul is still incipient, as well as there are few studies on the biogeographic patterns for these groups in the Neotropical region, especially for Mesembrinellidae. In this context, the first part of this study was aimed to conduct a fauna survey analysis for these families in two localities of the Rio Grande do Sul state, one in the Horto Botânico Irmão Teodoro Luis, in the municipality of Capão do Leão, and the other in the National Forest (FLONA) of São Francisco de Paula. Field collections were conducted using four Van Someren-Rydon traps baited with chicken or cattle liver. In the Horto Botânico, monthly collections were made for one year period (august/2018 to august/2019), with the traps exposed for seven days in the field. In FLONA, a single collection was made in the period from april 13th to may 03rd of 2019 (21 days). In the Horto Botânico, a total of 604 specimens were collected, with Lucia eximia being the most abudant species (57,3%), followed by Chrysomya albiceps (21,0%). In FLONA, 243 specimens were collected, with L. eximia being again the most abundant species (71,2%), followed by Hemilucilia semidiaphana (18,5%). Mesembrinellidae specimens were collected solely in the FLONA locality. Besides, in the Horto Botânico, it was possible to evaluate the temporal variation in the species profile, with the highest richness being observed in the autumn and spring months. The second part of this study was aimed to conducted a biogeographic analysis of Mesembrinellidae. For this, occurrence data for the 53 known living species of the family were compiled from the scientific literature and from material collected and available at the Laboratório de Genética e Evolução de Insetos (LEGIN), of the IB/UFPel. The occurrence data were used to elaborate distribution maps and latter were included in the biogeographic analyses conducted with the BioGeoBEARS software, using the models DEC, DIVA-like and BAYAREA. For the analyses, a phylogenetic tree with divergence time estimations was extracted from an unpublished phylogenetic analysis of Oestroidea relationships, conducted with the software BEAST. The results show that Mesembrinellidae originated around 38 million years ago, with the family’s ancestor lineage initially stablishing and diversifying in the northwest region of South America, associated with the Amazon Forest and the Andes Cordillera. The colonization of more peripheric areas of the Neotropical region, such as the Central America and the Atlantic Forest, occured in a more recent time, coinciding with the formation of the Panama Isthmus and with the occurrence of historical interconnections between the Amazon and Atlantic Forests, respectivelly.