Allobates femoralis (Boulenger, 1884)

Schiesari, Luis, Rossa-Feres, Denise De Cerqueira, Menin, Marcelo & Hödl, Walter, 2022, Tadpoles of Central Amazonia (Amphibia: Anura), Zootaxa 5223 (1), pp. 1-149 : 24-25

Allobates femoralis

External morphology. Description based on nine tadpoles between Stages 34 and 38 (LCS 458, 577, 706). Total length 29.1 ± 1.3 mm (mean ± 1 standard deviation SD; N = 4 tadpoles at Stages 36 and 37). Body oval in dorsal view and globular/depressed in lateral view ( Fig. 4A, B ). Snout rounded in dorsal view and truncate in lateral view. Eyes small, dorsally positioned and dorsolaterally directed. Nostrils small, circular, dorsally positioned closer to snout than to eyes, with opening laterally directed, without a projection on marginal rim. Oral disc ( Fig. 4C ) anteroventral, laterally emarginate; marginal papillae conical, uniseriate, with a wide dorsal gap. Submarginal papillae absent. LTRF 2(2)/3(1); A1 and A2 of the same length; P3 slightly shorter than P1 and P2. Jaw sheaths narrow, finely serrate; the anterior jaw sheath arch-shaped, posterior jaw sheath U-shaped. Spiracle single, sinistral, cylindrical, short and wide, posterodorsally directed, opening on the middle third of the body with the centripetal wall fused to the body wall, and longer than the external wall. Vent tube long, dextral, fused to the ventral fin, with dextral opening. Caudal musculature of moderate width; in lateral view gradually tapering to a pointed tip. Dorsal fin shallow, convex and originating at the tail-body junction; ventral fin shallow and parallel to the ventral margin of caudal musculature. Tail tip pointed. Lateral lines visible.

Colour. In preservative, body brown or grayish brown, belly transparent, digestive tract visible; caudal musculature creamy colored and tail fins translucent; both caudal musculature and fins covered with melanophores forming many brown or grayish brown blotches. In life, dorsum grayish brown, lateral of the body with chromatophores forming small silvery spots, venter translucent; caudal musculature pale brown with melanophores forming blotches, tail fins translucent ( Fig. 4D ).

Variation. LTRF 2(2)/3(1) from Stage 32 onwards. At Stage 27 LTRF ranges from 1/2 to 2/2 to 2(2)/3(1).

Metamorphs. Dorsum gray to black with a light brown dorsolateral line barely reaching the end of the body; belly with irregular dark markings; orange patch on the outside of the thigh and a yellow patch on the base of the anterior arm ( Fig. 4E ).

Natural history. Eggs are deposited in the forest floor between fallen leaves. Clutches contain from 8 to 17 pigmented eggs ( Lima et al. 2012). Tadpoles at Stage 27 are carried on the back of the males ( Lima et al. 2012) and rarely females ( Ringler et al. 2015) to small, temporary, isolated or streamside ponds and puddles in terra-firme forests and forest edge (this study). Larvae are found in all months of the year. Larvae are benthic and camouflaged against the substrate. Larvae consume detritus ( Weygoldt 1980) and anuran eggs ( Magnusson & Hero 1991). In experiments larvae were found to be preyed upon by dragonfly larvae and fish ( Gascon 1992a).

Comments. Tadpoles of A. femoralis were previously described by Duellman (1978) from Ecuador, by Hero (1990) from Central Amazonia, Brazil and by Duellman (2005) from Peru. Tadpoles described herein differ from those described by Duellman (1978) by presenting LTRF 2(2)/3; and from those described by Duellman (2005) by presenting dorsal fin originating on the tail and a rounded tail tip (although Fig. 13.2E in Duellman 2005 shows a tadpole with a pointed tail tip). There are no morphological differences between tadpoles herein characterized and those from Central Amazonia, Brazil, illustrated in Hero (1990).

Figures

FIGURE 4. Tadpole of Allobates femoralis (LCS s/n) at Stage 37: (A) lateral view, (B) dorsal view (scale = 10 mm), (C) oral disc (scale = 1 mm). (D) Dorsal view of live tadpole and (E) dorsolateral view of newly metamorphosed froglet. Pictures taken in captivity.

FIGURE 13. Tadpole of Ceratophrys cornuta (MNRJ s/n) at Stage 38: (A) lateral view, (B) dorsal view (scale = 10 mm), and (C) oral disc (scale = 1 mm).