Frostius erythrophthalmus

description

Description of holotype. Body robust, without clear subdivision between head and body in dorsal view (Fig. 1); head as wide as long; snout truncate in dorsal view, protruding in profile (Fig. 2); nostrils not protuberant, located slightly below the canthus rostralis, directed laterally; internarial distance smaller than eye-tonostril distance, eye diameter, and interorbital distance, about the same size of the upper eyelid width, and larger than the tympanum diameter; eye-to-nostril distance approximately equalling eye diameter and larger than the upper eyelid width; interorbital distance about twice the tympanum diameter; tympanum circular, with a weak supratympanic ridge; tympanum large, its diameter 69 % of eye diameter; eyes slightly protuberant, upper eyelid width about 65 % of interorbital distance; parotid glands and cranial crests absent; canthus rostralis straight; loreal region concave; choanae circular, large; tongue long, narrow, adherent by a small portion in front, extensively free behind. Forelimbs long, slender; forearms slightly more robust than arms. Hand (Fig. 2) large; fingers slender, not fringed nor webbed, with apical discs poorly developed; proximal phalange

New species of toad, genus Frostius Cannatella, 1986, from the Atlantic Rain Forest of Bahia, Brazil (Amphibia, Anura, Bufonidae)

diagnosis

Diagnosis. The species is characterized by: (1) dorsal surfaces dark gray, almost black; (2) ventral surfaces black, except for the yellow ventral face of thighs in life; (3) iris red in life; (4) tympanum large (mean TD / ED 0.69), circular; (5) fingers and toes short, slender, with poorly developed apical discs; (6) dorsal skin rugose, with rounded warts; (7) parotid glands absent. Frostius erythrophthalmus sp. nov. is readily distinguished from F. pernambucensis by its dorsal surfaces being dark gray, ventral surfaces black, iris red in life, digits looking short (proximal phalanges of fingers I and IV and of toes I, II, III, and V seem “ embedded ” into hand and foot), digits slender, with poorly developed apical discs, and tympanum large (mean TD / ED 0.69, range 0.54 – 0.90), circular. In F. pernambucensis, dorsal and ventral surfaces are brown to light brown, the iris is yellow in life, digits are long, laterally expanded, with developed apical discs, and the tympanum is small (mean TD / ED 0.54, range 0.34 – 0.66), vertically elliptical (Fig. 3).

New species of toad, genus Frostius Cannatella, 1986, from the Atlantic Rain Forest of Bahia, Brazil (Amphibia, Anura, Bufonidae)

discussion

Remarks. In describing Atelopus pernambucensis, Bokermann (1962) reported that it was not possible to relate it to other species then included in Atelopus and that its small size and absence of color pattern were unique. Cruz and Peixoto (1982) later described the tadpole of A. pernambucensis and, based on data on the biology and larval characters, affirmed that the species probably deserved a different generic status. Cannatella (1986) concluded that the species was unique by having an external tympanum and proposed the new genus Frostius for it. The new genus was considered a sister-group to Atelopus Duméril and Bibron or, alternatively, the sister-group to Atelopus + Osornophryne Ruiz-Carranza and Hernández-Camacho. The relationships still remain unsolved, since Frostius was not included in the phylogenetic approaches of Graybeal (1997) or Frost et al. (2006). Anuran communities in southern Bahia have been studied since the first expeditions of European naturalists to Brazil, like Wied (1821, 1824) and Spix (1824). These collections, although limited in geographic range, launched the basis for the taxonomic studies of many Brazilian anurans, some of them described from Bahia. Af

New species of toad, genus Frostius Cannatella, 1986, from the Atlantic Rain Forest of Bahia, Brazil (Amphibia, Anura, Bufonidae)

distribution

Distribution. Frostius erythrophthalmus sp. nov. is known from four localities in the Atlantic Rain Forest Domain in southern Bahia, at altitudes between 140 and 920 m above sea level. It extends the distribution of the genus ca. 190 km southwards to the Municipality of Boa Nova in the State of Bahia (Fig. 3; Appendix). The northernmost locality known for F. erythrophthalmus sp. nov. (EEE Nova Esperança, Municipality of Wenceslau Guimarães) is only 88 km distant from the southernmost known locality of F. pernambucensis (Serra da Jibóia, Municipality of Santa Terezinha; Juncá & Freitas, 2001). During the comparative analysis, we found in MNRJ a young specimen of F. pernambucensis from the Municipality of João Pessoa, State of Paraíba, northeastern Brazil, extending the distribution range of the genus 105 km airline northwards (Fig. 3; Appendix). Although it was a young specimen, it could readily be identified by its small, vertically elliptical tympanum, which we find to be a diagnostic character for F. p e r - nambucensis.

New species of toad, genus Frostius Cannatella, 1986, from the Atlantic Rain Forest of Bahia, Brazil (Amphibia, Anura, Bufonidae)