Phylogenetic relationships of the genus Mischonyx Bertkau, 1880, with taxonomic changes and three new species description Opiliones: Gonyleptidae)

Autor(es)

Gueratto, Caio ^[1] ; Benedetti, Alipio ^{[1, 2]} ; Pinto-da-Rocha, Ricardo ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Biociencias, Dept Zool, Sao Paulo - Brazil

^[2] Ctr Univ Metodista Izabela Hendrix, Belo Horizonte, MG - Brazil

• Tipo de documento: Artigo Científico
• Fonte: PeerJ; v. 9, SEP 28 2021.
• Citações Web of Science: 0

Resumo

The type species of Mischonyx Bertkau 1880, Mischonyx squalidus, was described based on a juvenile. The holotype is lost. Based on a revision of publications, the genus includes 12 species, all in Brazil. The objectives of this research are: to propose a phylogenetic hypothesis for Mischonyx based on Total Evidence (TE); propose taxonomic changes based on the phylogeny; and analyze the phylogenetic hypothesis biogeographically. Using the exemplar approach to taxon selection, we studied 54 specimens, 15 outgroups and 39 ingroup taxa using seven molecular markers (28S, 12S and 16S ribosomal genes, citochrome oxidase subunit I gene, carbamoyl-phosphate synthetase gene, internal transcribed spacer subunit 2 and histone H3 gene), totaling 3,742 bp, and 128 morphological characters. We analyzed the dataset under three optimality criteria: Maximum likelihood (ML), Maximum parsimony (MP) and Bayesian. We discuss the transformation of character states throughout the phylogeny, the different phylogenetic hypotheses using different datasets and the congruence of evidence between the Glades obtained by the phylogenetic analysis and the biogeographical hypothesis for the Atlantic Forest areas of endemism. We estimate that Mischonyx dade diverged 50.53 Mya, and inside the genus there are two major clades. One of them cointains species from Parana., Santa Catarina, South of Sao Paulo and Serra do Mar Areas of Endemism and the other has species from Espinhaco, Bocaina, South coast of Rio de Janeiro and Serra dos orgaos Areas of Endemism. The first split inside these two clades occurred at 48.94 and 44.80 Mya, respectively. We describe three new species from Brazil: Mischonyx minimus sp. nov. (type locality: Petropolis, Rio de Janeiro), Mischonyx intervalensis sp. nov. (type locality: Ribeirao Grande, Sao Paulo) and Mischonyx tinguaensis sp. nov (type locality: Nova Iguacu, Rio de Janeiro). The genus Urodiabunus Mello-Leitao, 1935 is considered a junior synonym of Mischonyx. Weyhia spinifrons Mello-Leittio, 1923; Weyhia clavifemur Mello-Leitao, 1927 and Geraeocormobius reitzi Vasconcelos, 2005 were transferred to Mischonyx. Mischonyx cuspidatus (Roewer, 1913) is a junior synonym of M. squalidus Bertkau, 1880. In the results of the phylogenetic analyses, Gonyleptes antiquus Mello-Leitao, 1934 (former Mischonyx antiquus) does not belong in Mischonyx and its original combination is re-established. As it is now defined, Mischonyx comprises 17 species, with seven new combinations. (AU)

• Processo FAPESP: 13/50297-0 - Dimensions US-BIOTA São Paulo: integrando disciplinas para a predição da biodiversidade da Floresta Atlântica no Brasil
• Beneficiário: Cristina Yumi Miyaki
• Modalidade de apoio: Auxílio à Pesquisa - Programa BIOTA - Temático