Flea Toad

description

Description of holotype. Body slender, leptodactyliform (Fig. 1). Head wider than long, its length 38 % of snout – vent length; snout long with length almost equal to eye diameter, rounded in lateral and dorsal views (Fig. 2 A – B); nostrils directed anterolateraly, elliptical, elongated, almost perpendicular to the canthus rostralis; canthus rostralis rounded; loreal region weakly concave; lips nearly sigmoid; eye slightly protruding in dorsal and lateral views, eye diameter 42 % of head length; tympanum indistinct; vocal sac indistinct and vocal slits absent; tongue longer than wide, free behind; choanae relatively small, rounded; vomerine odontophores absent. Upper arm and forearm relatively slender, upper arm approximately as long as forearm; fingers I and IV absent; finger II distinct, short; finger III long, robust; tip of finger II nearly rounded, tip of finger III pointed; relative lengths of fingers II <III; no webs or disks on fingers or toes; subarticular tubercles and inner and outer metacarpal tubercles absent (Fig. 2 C). Legs relatively short, thigh robust; thigh length 50 % of SVL, tibia length 88 % of thigh length; toes I, II and V externally absent, toe III robust,

A new species of flea-toad, genus Brachycephalus Fitzinger (Amphibia: Anura: Brachycephalidae), from the Atlantic rainforest of southern Bahia, Brazil

diagnosis

Diagnosis. The new species is promptly included in the genus Brachycephalus by the small body size (snout – vent length less than 18 mm), reduced number of toes, terminal digits not expanded, toes without circumferential grooves, and digits apically pointed. Brachycephalus pulex is diagnosed from all its congeners by the combination of the following character states: (1) toe II externally absent; (2) toe V vestigial; (3) fingers I and IV externally absent; (4) body leptodactyliform; (5) small body size (adult specimens SVL 8.0 – 8.4 mm); (6) dorsal ground color maculated with variegated browns without yellow or orange vivid colors; (7) dorsum with a x-shaped mark from posterior corners of eyes to sacral region; (8) an inverted depigmented v-shaped mark on chest, bordered above by a dark brown stripe on each side; (9) smooth skin texture with no dermal co-ossification on top of the head and central part of the back body. Comparisons with other species. Brachycephalus pulex is closely allied to B. didactylus and B. hermogenesi by the small body size (combined SVL of B. didactylus and B. hermogenesi 8.6 – 10.2 mm; B. pulex 8.0 – 8.4 mm), body leptodactyliform, dorsal ground color macu

A new species of flea-toad, genus Brachycephalus Fitzinger (Amphibia: Anura: Brachycephalidae), from the Atlantic rainforest of southern Bahia, Brazil

discussion

Remarks. The northern geographic distribution limit of the genus Brachycephalus deserves some considerations. Hedges et al. (2008) stated that the genus Brachycephalus is restricted to the Atlantic Coastal Forest in the states of Rio de Janeiro, São Paulo, and Paraná in southeastern Brazil. In the same article, the authors provided a map with the geographic distribution of the genera Brachycephalus and Ischnocnema, in which the range distribution of the former extends to near the Brazilian State of Alagoas (ca. 10 o S). This mapped geographic distribution is contradictory to the information presented in the article itself and is not congruent with the literature, as the northernmost geographic distribution limit known for the genus Brachycephalus is that of B. alipioi in the municipalities of Vargem Alta, Forno Grande and Santa Teresa (ca. 20 o S), all in the State of Espírito Santo, Brazil (Pombal & Gasparini 2006), and that of B. ephippium in the Serra do Brigadeiro (ca. 20 o S) (Pombal 2001; Dayrell et al. 2006), a regional designation of the Serra da Mantiqueira mountain range in the State of Minas Gerais, Brazil. Dayrell et al. (2006) and Frost (2010) included in the geographi

A new species of flea-toad, genus Brachycephalus Fitzinger (Amphibia: Anura: Brachycephalidae), from the Atlantic rainforest of southern Bahia, Brazil

etymology

Etymology. The specific name (pulex), a noun in apposition, refers to the flea, Pulex irritans, and is allusive to the small size and to the striking capacity for large leaps presented by the new species. Geographic distribution and Natural History. Brachycephalus pulex is only known from the type locality, a forest remnant located in a mountain range regionally named Serra Bonita, with elevations ranging from 200 to 950 m above sea level, which leads to altitudinal changes in the vegetation, from evergreen forest with elements of moist lowland semi-deciduous forest, to moist submontane forest near the summits. The Serra Bonita mountain range lies in the municipalities of Camacan and Pau Brasil, in the State of Bahia, Brazil, and is one of the last remnants of moist submontane forest in the region. It covers an area of approximately 7,500 hectares, 130 km from the city of Ilhéus on the Atlantic coast and 526 km from the State capital of Salvador. Approximately 50 % of the land cover is primary forest, and the remaining is a mosaic of forests in advanced stages of recuperation mixed with ‘ cabruca’ (cocoa trees planted under natural forest canopy) and small areas of pasture. In the

A new species of flea-toad, genus Brachycephalus Fitzinger (Amphibia: Anura: Brachycephalidae), from the Atlantic rainforest of southern Bahia, Brazil