Guiana Shield Leaf Toad

description

Description of holotype. MNHN 2006.2608 (Fig. 5). SVL 38.3 mm; HW 14.6 mm at angle of jaws; head shorter than wide, HL 12.8 mm. In dorsal view, snout acuminate, protruding and rounded in lateral view, with pointed vertical fleshy ridge from tip of snout to mouth; canthus rostralis strongly concave, smooth, without crests; top of head flat; cephalic crests poorly developed; paratoid poorly developed, elongated posteriously; eyelid thick, wide, densely tuberculate; nares slightly protuberant, directed dorsolaterally; corner of mouth very angular; tympanum clearly visible, ovoid. Skin of dorsum and limbs covered with high spicules, more numerous on outer edges of limbs, eyelids, and jaws; sides with a lateral row of large tubercules. Forelimbs slender, relatively long, digits long; tips of digits slightly bulbous; lengths of fingers 4 <1 = 2 <3; webbing basal; edge of webbing spinulous; thenar (metacarpal) tubercule ovoid, subarticular and supernumerary tubercules present (Fig. 5). Hindlimbs slender, inner metatarsal tubercle ovoid, approximately two times as large as outer; plantar surface with conical subarticular and many supernumerary tubercles. Length of toes 1 <2 <3 <5 <4, webbi

Description of two new species of Rhinella (Anura: Bufonidae) from the lowlands of the Guiana shield

diagnosis

Diagnosis. A medium sized species of the R. margaritifera species group as defined genetically by Fouquet et al. (2007) and morphologically by Hoogmoed (1990) and Vélez-Rodriguez (2004). It is distinguished from all other species of this complex by the following combination of characters (Fig. 5): (1) SVL of two females 43.7 ± 0.8 mm, of eight males 34.6 ± 4.3 mm; (2) bony knob at angle of jaws absent, corner of mouth angular; (3) canthus rostralis smooth, concave laterally, without crests; (4) heel not reaching posterior margin of eye when hindlimbs adpressed; (5) cephalic crests low; (6) neural spines indistinct; (7) tympanum large but smaller than eye diameter, round in males, ovoid in females; (8) paratoid glands relatively small, elongated posteriorly; (9) upper eyelid without projections; (10) toes about three-quarters webbed, three phalanges free on toe 4; (11) tarsal fold absent; (12) skin densely tuberculate, particularly on limbs, less between eyes and center of back in females; tubercules conical with small keratinized spicules; (13) oblique row of tubercules present from posterior corner of pratoid glands to groin; (14) snout pointed with fleshy soft ridge extending to

Description of two new species of Rhinella (Anura: Bufonidae) from the lowlands of the Guiana shield

distribution

Distribution and Ecology. Rhinella lescurei is only known from French Guiana, i. e. the southwestern (Haute Wanapi and Mitaraka), central (Saül), western (Litany) and northeastern portions (Cisame camp on Approuague river, Pararé station on Aratai river). Localities range from 20 to 170 m above sea level. During the rainy season (from November to January and from March to May), males call during day time within 10 meters of slowly running water. Calling males are usually isolated from each other and perched between 0.3 and 1 m high on a vine, dead trunk or root. Amplexus is axillary. Rhinella lescurei probably occurs in southeastern Suriname and Brazilian areas adjacent to French Guiana and Suriname. Preliminary results of an analysis of genetic data spanning the distribution of the R. margaritifera group suggest that this taxon could be endemic to the Guiana Shield (Fouquet et al., 2007; authors’ unpubl. data).

Description of two new species of Rhinella (Anura: Bufonidae) from the lowlands of the Guiana shield

etymology

Etymology. The name of the species honors the herpetologist Jean Lescure who has worked in French Guina for decades and is considered the most important founder of French Guianan herpetology.

Description of two new species of Rhinella (Anura: Bufonidae) from the lowlands of the Guiana shield