Astylosternus cf. fallax Amiet, 1978

Griesbaum, Frederic, Hirschfeld, Mareike, F. Barej, Michael, Schmitz, Andreas, Rohrmoser, Mariam, Dahmen, Matthias, Muehlberger, Fabian, Christoph Liedtke, H., L. Gonwouo, Nono, Doumbia, Joseph & Roedel, Mark-Oliver, 2019, Tadpoles of three western African frog genera: Astylosternus Werner, 1898, Nyctibates Boulenger, 1904, and Scotobleps Boulenger, 1900 (Amphibia, Anura, Arthroleptidae), Zoosystematics and Evolution 95 (1), pp. 133-160 : 137-138

Astylosternus cf. fallax Amiet, 1978

Material examined.

ZMB 82867 (GenBank MK318852), Gosner stage 25, Cameroon, foot of Mt Nlonako, Ekomtolo, 477 m, 4°49'58.46"N, 9°55'33.42"E, 24 November 2011, leg. M.F. Barej, H.C. Liedtke, N.L. Gonwouo & M. Hirschfeld.

The tadpole was caught in a forest stream. The genotyped tadpole has been compared with the two adults from Mount Nlonako, Cameroon (ZFMK 81164 and ZFMK 81608; GenBank MK318853, MK318854). The tadpole was genetically identical to these adults (compare Taxonomic remarks in the description of the A. fallax tadpole).

Description.

Long slender tadpole with long, muscular tail (Fig. 5); body oval in dorsal view, bullet-shaped in lateral view; snout rounded in dorsal and lateral view; body length 31.7% of total length; body height 34.9% of body length; body width 48.4% of body length; eyes positioned dorsolaterally, eye diameter 10.7% of body length; nostrils positioned dorsolaterally, closer to snout tip than to eyes; inter-nostril distance 86.7% of interorbital distance; tail fins narrow, dorsal and ventral fin originating from tail base; ventral fin height narrower, 73.2% of dorsal fin height; highest part of tail approximately at two-thirds of the tail; body height 72.3% of maximum tail height; tail axis width 52.6% of body width; tail axis height 65.3% of maximum tail height; tail tip pointed; vent tube dextral; body with lateral sacs, extending from spiracle to end of body; short spiracle, sinistral; mouth positioned rostroventral, narrower than interorbital distance; keratodont formula 1:2+2+2/2+2:1; anterior lip with lateral papillae and big rostral gap; posterior lip with 2 or 3 rows of ca 20 massive papillae, papillae of marginal row are distinctly longer than of inner rows (Fig. 5c); black jaw sheaths massive and serrated; upper jaw sheath with a small medial fang, lower jaw U-shaped with a broad medial notch.

The tadpole (Gosner stage 25) measures 97.4 mm in total length.

Coloration in preservation.

Basic color light brown with darker and speckled dorsal surface; venter light and grayish with few or no dark speckling; tail fins beige, semitransparent with irregular tiny dark brown spots. In life the color was of a duller, darker brown (Fig. 6).