Redefining the Mexican genus Diguetinus Roewer, 1912 (Opiliones, Phalangioidea, Globipedidae) based on morphology and molecular phylogenetic data, with the redescription of Diguetinus spinulatus (Banks, 1898) stat. restit.

The genus Diguetinus Roewer, 1912 (Opiliones, Globipedidae) is a monotypic genus that includes the widespread species Diguetinus raptator Roewer, 1912 from Mexico. Some studies have suggested that additional species could be included within the genus, particularly Metopilio spinulatus (Banks, 1898). This species has a brief but complicated taxonomic history, being originally described in Leptobunus Banks, 1893, considered in Hadrobunus Banks, 1900, later transferred to Diguetinus and currently in Metopilio Roewer, 1911, all changes without a solid justification. The aim of this study was to conduct a morphological revision of D. raptator and M. spinulatus using specimens from their respective type localities. In addition, a phylogenetic hypothesis that includes D. raptator and M. spinulatus, was inferred based on partial sequences of the mitochondrial gene cytochrome c oxidase subunit I (COI) gene. Our results indicate that D. raptator and M. spinulatus are related in a clade that leads to the phylogenetic redefinition of Diguetinus. Accordingly, the following taxonomic changes are proposed: a) a new diagnosis of Diguetinus; and b) the redescription of Diguetinus spinulatus stat. restit. (♂, ♀). Also, comparative detailed illustrations of the male and female genitalia of these species are provided, including taxonomic comments on the use of previous characters for the diagnosis of Diguetinus and Metopilio. Finally, we provide evidence of intrasexual dimorphism in males of D. raptator.