Abai, MR

6th International Congress of DipterologySouth American Biogeography: a panbiogeographic andcladistic approach to the Muscidae and AnthomyiidaeCarvalho, C.J.B. deBiodiversity and Biogeography Laboratory, Department of Zoology, UniversidadeFederal do Paraná, Curitiba, 81.531-980, BrazilToday, the Muscidae and Anthomyiidae are understood to be sister-groups,both of which occur naturally in all except arctic regions. In theNeotropical region, more than 850 species of Muscidae are found in allenviroments, from above 3000 m in the Andes to sea level, where a fewspecies are found in rocks sprinkled by the sea. To understand SouthAmerican biogeography, two main questions arise: 1) why do species havespecific distributions?; and 2) why do unrelated groups have similardistribution patterns? In attempting to answer these questions, we can askwhat are the main processes that caused those patterns. In answer, threemain processes are important: dispersal, vicariance and extinction. Thedistribution patterns for some species of Muscidae in the genera ApsilMalloch, Bithoracochaeta Stein, Brachygasterina Macquart, CyrtoneurinaGiglio-Tos, Cyrtoneuropsis Malloch, Micropotamia Carvalho, PalpibracusRondani, Polietina Schnabl & Dziedzicki, Reynoldsia Malloch andSouzalopesmyia Albuquerque were analysed by panbiogeographical andbiogeographical cladistic methods. In contrast, the Anthomyiidae is a lessdiverse family in South America, with fewer than 100 described species.Only Coenosopsia Malloch has been studied using cladistic andbiogeographic approaches. The biogeographical pattern of this genussupports the general proposed pattern for the area. This pushes back theorigin of the genus in South America. In conclusion: 1) the pattern of theapparent disjunct distributions of some Muscidae and Anthomyiidaespecies are due to incomplete sampling; 2) more described biogeographicpatterns are necessary for consistent comparisons and pattern resolution; 3)regardless, incongruencies may still arise (after better and more sampling)if events of different ages caused those patterns; 4) therefore, we shouldlook to molecular phylogenetic data that may help estimate divergence36