First comprehensive approach to the systematics of <i>Myotis barquezi</i> using morphology, molecules, and acoustics

Abstract The genus Myotis comprises a diverse group of vespertilionid bats distributed almost worldwide. In Argentina, 15 species have been recorded, with Myotis barquezi one of the most recently described, and reported only from the Southern Andean Yungas ecoregion. We present the first dataset integrating morphological, molecular, and acoustic information for M. barquezi, aimed at improving species delimitation and clarifying its phylogenetic placement within the ruber species group. Additionally, we report a second geographic record for M. barquezi, which significantly extends its known range (ca. 930 km SE). Specimens of Myotis were collected in Corrientes province, and their characteristics are coincident with those described for M. barquezi. The acoustic parameters were consistent with those reported for the genus Myotis worldwide, characterized by wide broadband frequency-modulated (FM) pulses, with minimal constant frequency. Phylogenetic analyses based on the cytochrome b (Cytb) and cytochrome C oxidase I (COI) genes, employing both single-locus and multilocus approaches, identified a well-supported monophyletic clade distinct from other species within the ruber species group. These integrative findings provide critical insights into the systematics and distribution of M. barquezi and underscore the need for further research on this species.