SISTEMÁTICA DE OCYDROMIINAE SCHINER (DIPTERA: EMPIDOIDEA: HYBOTIDAE)

Abstract

Ocydromiinae is a monophyletic subfamily of Hybotidae (Diptera: Empidoidea) with a cosmopolitan distribution that include 15 genera and 102 valid species, supported by synapomorphies: male terminalia with flexible and articulated apical phallus and fully articulated surstylus. The monophyly of Ocydromiinae is considered well established, but the lack of a phylogenetic analysis including all known genera of subfamily results in the absence of a cladistic relationship between the genera, compromising the establishment of limits among them. Thus, non-studied genera since creation and the absence of information and illustrations of male and female terminalia makes difficult new species description. In this context, this study proposes to clarify the relationship and delimitation between Ocydromiinae genera by phylogenetic analysis with adult morphological characters with worldwide specimens sampling and also provide updated diagnoses and a identification key for subfamily genera. In addition, we propose a taxonomic review of Pseudoscelolabes, the Scelolabes redescription with addition of two new species, followed by a discussion about its relationship with Hoplopeza, a first record of Leptopezella from Brazil, a taxonomic study of Leptodromia, a neotropical Chvalaea specimens’ study and its new record for the Australasian Region. The phylogenetic study was based on the specimens’ analysis and the original descriptions, in which 73 morphological characters of the head, thorax and abdomen (including male and female terminalia) were coded in 48 terminal taxa (44 from the inner group and 4 from the outer group), of which eight taxa were analyzed using data available in literature and images provided by the entomological collections. The cladistic parsimony analysis using implicit weighting (k= 6.484375) returned a more parsimonious tree with 197 steps. In Ocydromiinae, Neotrichina was corroborated as the most basal genus, and the following relationships were recovered in the subfamily: Neotrichina + (Ocydromia + (Austropeza + ((Leptopeza + Pseudoscelolabes) + (Leptodromiella + (Leptodromia + (((Abocciputa + Apterodromia) + (Brazilodromia gen. nov. +(Parachvalaea gen. nov. + Chvalaea))) + (Oropezella (Leptopezella + (Scelolabes +Hoplopeza))))))))), while Stylocydromia was classified as Incertae sedis due to impossibility of specimens access. Two new genera were created: Brazilodromia gen. nov. to realocate O. amazonica and Parachvalaea gen. nov. to realocate O. abdominalis, transferred to avoid paraphyllism of Oropezella. In this new composition, Ocydromiinae now has 17 monophyletic genera, of which seven are monotypic.