Revisão taxonômica do complexo de espécies Crossodactylus trachystomus (Reinhardt & Lütken 1862) na Serra do Espinhaço (Anura: Hylodidae)

Abstract

Hylodidae is composed by the genera Hylodes, Crossodactylus, Megaelosia and Phatasmarana that occur predominantly in the Atlantic Rain Forest. Crossodactylus is represented by 13 species, among them C. trachystomus is characterized by its small size, presence of a white or cream band from the muzzle to the shoulder, presence of a partial oblique lateral stripe and reticulate belly. The species is distributed throughout the Serra do Espinhaço, Minas Gerais. Pimenta et al. (2015) synonymized C. trachystomus and C. bokermanni based on morphological data from adults. However, Montesinos (2017) recovered two sister clades representing C. trachystomus with a genetic distance of 2%, questioning the synonymy of Pimenta et al. (2015). In addition, this author found a clade represented by specimens from the municipality of Olhos D'agua (MG), which may be a new species. We carried out an investigation of C. trachystomus populations, with morphological characterization analyzes of adults and tadpoles, vocalization, and molecular characterization of C. trachystomus populations along Serra do Espinhaço. For molecular analyses, the mitochondrial genes 12s and 16s were sequenced and a phylogeny was performed using the Maxima Likelihood optimality criterion. Here, we describe three morphotypic variations based on C. trachystomus adults: C. trachystomus Quadrilátero; C. trachystomus Espinhaço and C. trachystomus Olhos D’água. However, we did not find any other evidence (vocalization, larvae or phylogeny) that justifies separating them as different species. Based on morphological and genetic evidence, it was possible to verify that Caetité population represents a new species. The new species is distinguished from C. trachystomus by the absence of white stripe from the snout to the shoulder, by having a white belly and a reduced or absent partial oblique lateral stripe. Furthermore, Crossodactylus sp. nov was recovered as a sister lineage of C. trachystomus and has a genetic distance that varies from 2 to 4% of the other populations of C. trachystomus. Thus, we corroborate the hypothesis of Pimenta et al. (2015) for C. trachystomus and describe a new species of Crossodactylus.