Corythomantis

Abstract: A second species of casque-headed frog of the genus Corythomantis is described from northeastern Brazil. This new species is characterized by its canthus rostralis without ridge, head longer than broad, absence of granules on eyelid, discs of fingers and toes smallsized, dorsal color pattern with longitudinal stripes, dorsal skin smooth, presence of neopalatines, and nasals that conceal the alary processes of premaxillaries. The distribution of C. greeningi is reviewed based on collection and literature records. The only putative synapomorphy recognized for the genus Corythomantis are the nasals that conceal the alary processes of premaxillaries.

Abstract: The genus Corythomantis was monotypic for over 100 yr, encompassing only the species C. greeningi. In 2012, a second species, C. galeata, was described, but this species was recently reassigned to Nyctimantis, rendering Corythomantis once again monotypic. The geographic distribution of C. greeningi covers the Caatinga and Cerrado biomes from northeast Brazil, with a western limit in Tocantins state and a southern limit in Minas Gerais state. Here we demonstrate the existence of a second species of Corythomantis through molecular, acoustic, and morphological data. The new species differs in morphology from C. greeningi in head shape and tibia coloration. The new species has an advertisement call with shorter duration, higher pulse rate, and different acoustic structure. Mitochondrial deoxyribonucleic acid (DNA) data show a genetic divergence from C. greeningi of 2.88% in the 16S ribosomal DNA gene and 14.06% in the cytochrome oxidase I gene. The geographic distribution of the new species is restricted to the Espinhaco Mountain Range at elevations from 315 to 930 m above sea level.

Abstract: Nyctimantis galeata (Pombal, Menezes, Fontes, Nunes, Rocha & Van Sluys) is a casque-headed frog member of the Lophyohylini tribe (Blotto et al. 2020), narrow-endemic to the municipality of Morro do Chapeu, Bahia state, Brazil (Pombal et al. 2012). This species was initially described as sister of Corythomantis greeningi Boulenger based on shared osteological autapomorphies within Hylidae (see Faivovich et al. 2005; Pombal et al. 2012). However, in the most recent molecular phylogenetic analysis of Lophyohylini, Blotto et al. (2020) redefined the genus Nyctimantis to accommodate species from the former genus Aparasphenodon, Argenteohyla and “Corythomantis galeata” (as initially described; Pombal et al. 2012). Currently, the genus Nyctimantis comprises seven species: N. arapapa (Pimenta, Napoli & Haddad), N. bokermanni (Pombal), N. brunoi (Miranda-Ribeiro), N. galeata, N. pomba (Assis, Santana, Silva, Quintela & Feio), N. rugiceps Boulenger, and N. siemersi (Mertens). Among these, N. arapapa (Lourenco-de-Moraes et al. 2013), N. brunoi (Wogel et al. 2006) and N. siemersi (Cespedez 2000; Cajade et al. 2010) have their tadpoles described, while oral cavity anatomy was only reported for those of N. brunoi and N. siemersi (Wogel et al. 2006; Cajade et al. 2010). Considering that larval morphology generally provides reliable information for anuran systematic and taxonomic studies (Wassersug 1980; McDiarmid & Altig 1999; Haas 2003), a formal comparison of these larvae might highlight additional non-molecular evidence that support them as congeners (Blotto et al. 2020). Herein, we describe the external morphology and oral cavity anatomy of tadpoles of N. galeata and compare it with those of related species.