Revision of Tropopterus Solier: A disjunct South American component of the Australo-Pacific Moriomorphini (Coleoptera, Carabidae)

Abstract

TropopterusSolier, 1849, precinctive to southern South America, is taxonomically revised. Six new species are described:T. peckorumsp. nov.,T. robustussp. nov.,T. canaliculussp. nov.,T. trisinuatussp. nov.,T. minimucrosp. nov., andT. fieldianussp. nov.Merizodus catapileanusJeannel, 1962, is synonymized withT. montagneiSolier, 1849. Lectotypes are designated forT. montagnei,T. giraudyiSolier,T. duponcheliiSolier, andT. nitidusSolier (=T. duponchelii).Tropopterus peruvianusStraneo is noted as anomen dubium, with its identity and taxonomic placement to be substantiated via neotype designation. Phylogenetic relationships amongTropopterusspp. are hypothesized based on 37 morphological characters, the distributions of which are analyzed under the parsimony criterion, with the cladogram root established betweenTropopterusand its adelphotaxon from New South Wales, Australia. Speciation in the group has occurred predominantly at a limited geographical scale relative to the overall generic distribution, with three pairs of sister species sympatric. However phylogenetic divergence between taxa in the more northern, sclerophyllous forest characterized byNothofagus obliqua(Brisseau de Mirbel) and those occupying the Valdivian and North Patagonian Rain Forest dominated byN. dombeyi(Brisseau de Mirbel) is observed in two instances of phylogenetic history. Using specific collecting locality records, it is shown thatTropopterusbeetles have been collected syntopically and synchronically with species ofGlypholomaJeannel (Coleoptera, Staphylinidae),AnaballetusNewton, Švec & Fikáček (Coleoptera, Leiodidae),AndotypusSpangler (Coleoptera, Hydrophilidae), andNovonothrusBalogh (Acari, Oribatida). These concordant ecological occurrences document a cohesiveNothofagusforest leaf-litter community. These genera plus other Valdivian Rain Forest invertebrate taxa all exhibit an Austral disjunct biogeographical pattern that corroborates trans-Antarctic vicariance between theNothofagusforests of southern South America and Australia. Male genitalic antisymmetry is shown to be a synapomorphy ofTropopterus, though the female reproductive tract retains the plesiomorphic orientation observed in all other moriomorphine taxa.