Abstract

The type species of Mischonyx Bertkau 1880, Mischonyx squalidus, was described based on a juvenile, which holotype is lost. Based on revision publications, the genus includes 11 Brazilian species.
The objectives of this research are: to propose a phylogenetic hypothesis for Mischonyx based on Total Evidence (TE), to propose taxonomic changes based on the phylogeny and analyse the phylogenetic hypothesis biogeographically as well. We studied 54 individuals, 15 of external group and 39 of internal group for seven markers (28S, 12S, 16S, COI, CAD, ITS e H3), totalizing 3742 bp. we raised 128 morphological and genitalic characters. We analysed the dataset under two optimality criteria: Maximum likelihood (ML) and Maximum parsimony (MP).
We described three new species: Mischonyx minimus sp. nov. (type locality: Petrópolis, Rio de Janeiro), Mischonyx intervalensis sp. nov. (type locality: Ribeirão Grande, São Paulo) and Mischonyx tinguaensis sp. nov (type locality: Nova Iguaçu, Rio de Janeiro). The genus Urodiabunus is considered a junior synonym of Mischonyx. Weyhia spinifrons Mello-Leitão, 1923; Weyhia clavifemur Mello-Leitão, 1927 and Geraeocormobius reitzi Vasconcelos, 2005b were transferred to Mischonyx. M. cuspidatus Roewer, 1913 is a junior synonym of M. squalidus Bertkau, 1880. By the phylogenetic hypothesis of relationship, Gonyleptes antiquus Mello-Leitão, 1934 (former Mischonyx antiquus) cannot be considered a Mischonyx species, therefore we reestablish the original combination. The new composition for Mischonyx comprises 17 species, with 7 new combinations. We discuss the transformation of character states throughout the phylogeny, the different phylogenetic hypothesis using different datasets and the congruence of evidence between the clades in the phylogenetic hypothesis with the biogeographical hypothesis on Atlantic Forest areas of endemism.