Boana cinerascens (Spix, 1824)

Schiesari, Luis, Rossa-Feres, Denise De Cerqueira, Menin, Marcelo & Hödl, Walter, 2022, Tadpoles of Central Amazonia (Amphibia: Anura), Zootaxa 5223 (1), pp. 1-149 : 41-42

Boana cinerascens

External morphology. Description based on three tadpoles at Stages 33, 37 and 39 (LCS 576, 654). Total length 28.3 mm (Stage 37) and 33.0 mm (Stage 39). Body elongated oval in dorsal view and globular/depressed in lateral view ( Fig. 17A, B ). Snout rounded in dorsal and lateral views. Eyes medium-sized, dorsally positioned and dorsolaterally directed. Nostrils small, oval, dorsolaterally positioned, near to eyes, with opening anterolaterally directed, with a large triangular projection on the marginal rim. Oral disc ( Fig. 17C ) ventral, ventrolaterally emarginate; marginal papillae conical, uniseriate, with narrow dorsal and ventral gaps. Submarginal papillae absent. LTRF 2(1-2)/3-4(1); A1 and A2 of the same length; P2 slightly longer than P1; P3 slightly shorter than P2. P4, when present, very short. Jaw sheaths moderately wide, finely serrated; anterior jaw sheath arch-shaped, posterior jaw sheath V-shaped. Spiracle single, sinistral, conical, short and wide, posteriorly directed, opening in the medial third of the body, with the centripetal wall fused to the body wall and longer than the external wall. Vent tube medial, fused to the ventral fin, with a dextral opening. Caudal musculature of moderate width; in lateral view gradually tapering to a pointed tip. Dorsal fin of moderate height and convex, originating at the tail-body junction; ventral fin shallow, slightly convex. Tail tip pointed.

Colour. In preservative dorsum greenish brown with scattered rounded white chromatophores; caudal musculature light brown; fins translucent. In life body transparent olive brown with scattered white cromathopores; tail transparent with scattered white chromatophores ( Fig. 17D ) (Hero 1990).

Variation. LTRF 2(2)/3, 2(2)/3(1), 2(2)/3(1,2), or 2(1,2)/3(1) at Stages 25 and 26.

Metamorphs. In preservative unpigmented; skin translucent and musculature light cream; many white chromatophores on dorsum and sides and, to a lesser extent, venter; venter translucent; diffuse spots between eyes ( Fig. 17E ).

Natural history. Eggs are deposited in clumps in streamside ponds in terra-firme forests. Clutches contain from 165 to 298 pigmented eggs ( Lima et al. 2012; Telles et al. 2013). Tadpoles are found in streamside ponds and less frequently in streams in terra-firme forests. Tadpoles are found in most months of the year. In experiments tadpoles were found to be moderately oophagous and to be preyed upon by fish ( Hero 1991; Magnusson & Hero 1991).

Comments. Tadpoles were described as Hyla granosa by Duellman (1978) from Ecuador, Duellman (2005) from Peru and by Mijares-Urrutia (1993) from southeastern Venezuela, and illustrated by Hero (1990) from Central Amazonia. Tadpoles from Ecuador differ from those herein characterized by presenting body ovoid, spiracle lateroventral and posterodorsally directed, oral disc anteroventral and laterally emarginate, with a dorsal gap on marginal papillae, and LTRF 1(1)/2. According to Mijares-Urrutia (1993) this LRTF may be due to the early developmental stage (Stage 25) described by Duellman (1978). Tadpoles from Central Amazonia (Hero 1990; Plate 10) present LTRF 2(1,2)/3-4(1)[2] with a much shorter ventral gap than the tadpoles herein characterized. Tadpoles from Venezuela ( Mijares-Urrutia 1993) differ from those herein characterized by presenting marginal papillae biseriate with only a dorsal gap, LTRF 2(2)/4(1), and oral disc laterally emarginate. Tadpoles from Peru differ from those herein characterized by presenting body ovoid, nostrils without projection on marginal rim (“narial papillae” in Duellman 2005), spiracle posterodosally directed, dorsal fin originating on caudal musculature, marginal papillae irregularly biseriate posteriorly, and LTRF 2(2)/3(1).

Figures

FIGURE 17. Tadpole of Boana cinerascens (LCS 654) at Stage 37: (A) lateral view, (B) dorsal view (scale = 10 mm), and (C) oral disc (scale = 1 mm). (D) Dorsal view of live tadpole and (E) dorsolateral view of newly metamorphosed froglet.