Tadpoles of Central Amazonia (Amphibia: Anura) Author Schiesari, Luis 0000-0003-0814-591X lschiesa@usp.br Author Rossa-Feres, Denise De Cerqueira 0000-0002-4537-9064 denise.rossa-feres@unesp.br Author Menin, Marcelo 0000-0002-7209-5083 Author Hödl, Walter 0000-0003-0814-591X lschiesa@usp.br text Zootaxa 2022 2022-12-28 5223 1 1 149 http://dx.doi.org/10.11646/zootaxa.5223.1.1 journal article 222436 10.11646/zootaxa.5223.1.1 f19c5754-1a7b-4f9e-bdd8-70cc4bf3d1e4 1175-5326 7517957 2AF3B77E-408A-4104-A058-108101993EBC Lysapsus bolivianus External morphology. Description based on a tadpole at Stage 35 (LCS 597). Total length 24.5 mm . Body elongate oval in dorsal view and triangular/depressed in lateral view ( Fig. 32A, B ). Snout rounded in dorsal and lateral views. Eyes small, positioned and directed laterally. Nostrils small, circular, dorsolaterally positioned near to snout, with opening anterolaterally directed, without a projection on the marginal rim. Oral disc ( Fig. 32C ) terminal, ventrally emarginate; marginal papillae blunt, biseriate, with a dorsal gap. Submarginal papillae present laterally. LTRF 2(1,2)/3; A1 and A2 of the same length; P2 slightly longer than P1; P3 of about half the length of P2. Jaw sheaths moderately wide, finely serrated; anterior jaw sheath arch-shaped, posterior jaw sheath V-shaped. Spiracle single, sinistral, conical, short and wide, posterodorsally directed, opening in the medial third of the body, with the centripetal wall fused to the body wall and longer than external wall. Vent tube medial, very large, fused to the ventral fin, with a medial opening. Caudal musculature of moderate width; in lateral view gradually tapering to a pointed tip. Dorsal fin of moderate height, convex, originating on the posterior third of the body; ventral fin of moderate height, convex. Tail tip pointed. Colour. In preservative dorsum grayish brown with dark brown spots; caudal musculature cream and fins translucent, both with vertical brown bars. In life dorsum greenish brown with scattered brown spots; sides and venter silver; iris bright red; anterior 2/3 of tail largely unpigmented and translucent, contrasting with the posterior third of tail, which is entirely black ( Fig. 32D ). Variation. LTRF 2/3 or 2(2)/3 at Stages 30 and 31. Metamorphs. Metamorphs strongly resemble adults; color green with sparse gray marks and coppery red iris ( Fig. 32E ). FIGURE 32. Tadpole of Lysapsus bolivianus (LCS 597) at Stage 35: (A) lateral view, (B) dorsal view (scale = 10 mm), and (C) oral disc (scale = 1 mm). (D) Lateral view of live tadpole and (E) dorsolateral view of newly metamorphosed froglet. Natural history. Eggs were not observed in Central Amazonia. Gravid females contain on average 147 ovarian eggs (Ĥdl 1990). In Central Amazonia tadpoles of L. bolivianus are found in the root zone of floating meadows in várzea floodplain lakes. In the igapó flooded forests of eastern Amazonia tadpoles of L. bolivianus are found in both temporary and permanent lentic water bodies ( Azevedo-Ramos et al. 1999 ). Tadpoles are nektonic. Color pattern is presumably disruptive. Comments. Tadpoles described by Santana et al. (2013) from the State of Amapá , Brazil , differ from those herein characterized by presenting snout rounded to slightly acute in lateral view, nostrils elliptic, oral disc ventral and not emarginate, two rows of alternated marginal papillae (biseriate anteriorly, bi or triseriate laterally, and uniserate and short posteriorly), LTRF 2 (2)/3, 2(2)/3(1) and 2/3, tail fins low, dorsal and ventral fins almost parallel to the tail musculature . Genus Osteocephalus . Tadpoles of genus Osteocephalus found in Central Amazonia share the following combination of morphological characteristics: moderate size; body elongate oval or ovoid in dorsal view and globular or globular/depressed in lateral view; spiracle sinistral (ventrolateral in O. oophagus ); dorsal and ventral fins shallow or of moderate height; oral disc anteroventral with one row of marginal papillae (biseriate in O. oophagus ) except for a dorsal gap; submarginal papillae present; LTRF in variations of 2/3 and 2/5-7.