Echevarría, L. Y., D. J. Paluh, L. A. García-Ayachi, P. J. Venegas, A. Catenazzi, R. Pradel & S. Castroviejo-Fisher

Two new species of marsupial frogs (Anura: Hemiphractidae) from the Central Andes of northern Peru. pp. 1-23 plus Erratum (11 April 2022)

Abstract. We describe two new species of Gastrotheca from the humid montane forests and grasslands of La Libertad and Amazonas departments, respectively, in the northern portion of the central Peruvian Andes. Our phylogenetic analysis recovered the new species as part of the Gastrotheca marsupiata species group and closely related to G. gemma, G. oresbios, G. psychrophila, G. spectabilis, G. stictopleura, and one undescribed species. The new species from La Libertad department can be differentiated from the aforementioned congeners by being of moderately small size (SVL = 33.3–41.9 mm, N = 3), having an acutely rounded snout in dorsal view, a rounded snout in lateral view, smooth skin on the dorsum with low granules, and smooth tympanic annulus and supratympanic fold. The new species from Amazonas department (SVL = 33.5–43.9 mm, N = 2) differs from other Gastrotheca species by having the dorsum covered with large and closely packed rounded pustules, two prominent paravertebral longitudinal pustular ridges, and a distinctly thick and elevated supratympanic fold extending from the top edge of the tympanum to the flank and being continuous or fused with the dorsolateral row of elongated pustules. In addition to external morphological characters, we include detailed descriptions and illustrations of the skeleton of the holotypes based on 3D models obtained from CT-scans.

Key words. Amphibia, CT-scan, Gastrotheca, osteology, phylogeny, taxonomy.