Universidade de São Paulo

Graduate Student, Departamento de Biologia

Thesis Title: Cladistics analysis of the Orfeliini (Diptera: Keroplatidae: Keroplatinae)

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The Orfeliini (Diptera: Keroplatidae: Keroplatinae) are a group of fungus gnats distributed worldwide, currently with 51 genera and 538 described species. The tribe corresponds to 55% of the diversity of the family of Keroplatidae. The oldest fossil assigned to this tribe are from Eocene/Oligocene Baltic amber. The phylogenetic relationships in the Orfeliini are still poorly known and the taxonomic status of many genera remains uncertain. The circumscription of the tribe is still debatable, but it can be recognized by the following combination of characters, some of which are plesiomorphic: well developed or prolonged mouthparts; palpi with 1+4 articles (reduced in Planarivora Hickman and Asynaphleba Matile), the last palpomere never enlarged; antennae flattened (occasionally with pectination, as in Tamborinea Matile, Platyceridion Tollet and some species of Proceroplatus Edwards); prosternum bare (except in Lutarpya Edwards and in some species of Truplaya Edwards); macrotrichia dorsally on wing veins; larvae with a pair of anal lobes.  Loïc Matile had an outstanding contribution in the taxonomy of the Keroplatidae, with several studies on their morphology, systematics and biogeography. In his most remarkable monographic study, the Orfeliini were not included. He addressed the question of about the possible polyphyly of the Orfeliini, but regarded the subfamily itself as monophyletic. In the present study of the Orfeliini some poorly known genera are reviewed, an identification key for the genera is provided, and a phylogenetic study of the relationships of the genera of the tribe is performed. The data matrix has 60 taxa (5 outgroups), and 100 characters. Results show that the relationships among genera in parts of the tribe are unstable especially in the Orfelia-group and the Platyura-group. These results are congruent with Matile_partial analysis of the tribe and his personal appointments, showing that the Orfeliini would be paraphyletic regarding the Keroplatini. The probable paraphyly of different genera of the tribe makes clear that some of the problems at the level of alpha taxonomy cannot be solved without a better understanding of the phylogenetic relationships of the Orfeliini and Keroplatini. The solution for the phylogenetic relationships between the Orfeliini genera is particularly relevant because of the of biologies within the family, in great extension within the tribe itself, with larvae that are predatory and sporophagous, luminescent and non-luminescent, and cave dwellers and non-cave dwellers. Apparently, each of these features had many parallel origins and they are not associated among themselves, constituting a very challenging and complex case of habitus and habitat evolution.

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