Systematics of the Hyloxalus bocagei complex (Anura: Dendrobatidae), description of two new cryptic species, and recognition of H. maculosus

Abstract

The bocagei clade is a species complex of dendrobatid frogs evidenced from recent molecular systematic studies. This lineage is endemic to the eastern Andean slopes and adjacent Amazonian lowlands in southern Colombia, Ecuador and northern Peru. Herein, we analyze the taxonomy of the bocagei clade by means of qualitative and quantitative morphological characters and call parameters. We recognize and provide accounts for six species: Hyloxalus bocagei, H. faciopunctulatus, H. maculosus, H. sauli and two new species. We also provide phylogeographic data. We formally assign the name of Hyloxalus bocagei only to populations from the surroundings of Volcán Reventador (Provincia Napo, Ecuador). Additionally, we describe the tadpoles of Hyloxalus bocagei, H. maculosus, and two new species, plus vocalizations of H. bocagei, H. maculosus, H. sauli, and two new species. Morphological variation was estimated from 16 morphometric characters using multivariate analysis. Adults of the two new species were indistinguishable using quantitative and qualitatively morphological characters. Nevertheless, molecular data, call parameters (dominant frequency, note repetition rate), and tadpole morphology supported the recognition of these two species as cryptic taxa. A current phylogenetic tree using molecular characters of five species of the bocagei clade is also provided including the maximum likelihood (ML) phylogeny and a chronogram of the group. Our phylogeny confirms the close relationship of members of the bocagei clade with Andean relatives of Hyloxalus and recurrent dispersal events from the Andes to the Amazon Basin in the late Miocene (< 10 MYA). Our data also corroborate that the sister lineage of bocagei clade includes the Andean H. subpunctatus clade. We anticipate that further detailed morphological and molecular data will be necessary to reveal the existence of additional cryptic species within the bocagei clade.