Leptodactylodon ovatus orientalis Amiet, 1971

Mapouyat, Lissa, Hirschfeld, Mareike, Rödel, Mark-Oliver, Liedtke, H. Christoph, Loader, Simon P., Gonwouo, L. Nono, Dahmen, Matthias, Doherty-Bone, Thomas M. & Barej, Michael F., 2014, The tadpoles of nine Cameroonian Leptodactylodon species (Amphibia, Anura, Arthroleptidae), Zootaxa 3765 (1), pp. 29-53 : 40-41

Leptodactylodon ovatus orientalis Amiet, 1971

Nine tadpoles where examined. All were found in Ebo Forest at the Bekob and Njuma sites: ZMB 78534 (five tadpoles, Gosner stages 25 & 26, Ebo Forest Bekob, 4°21’51.96”N, 10°25’10.26”E, 893 m, 30 September 2011); ZMB 78535 (one tadpole, Gosner stage 25, Ebo Forest Bekob, 4°21’51.96”N, 10°25’10.26”E, 893 m, 10 September 2011); ZMB 78540 (one tadpole, Gosner stage 37, Ebo Forest Bekob, 4°21’55.68”N, 10°25’18.48”E, 825 m, 10 January 2011); ZMB 78541 (two tadpoles, Gosner stage 25, Ebo Forest Njuma, 4°20’59.34”N, 10°14’15.72”E, 311 m, 5 August 2011). All tadpoles were found in mid-sized rivers within primary and secondary forests, at 311 to 893 m.

The description is based on two genotyped individuals (ZMB 78534–35) of Gosner stage 25–26. Body length/ total length ratio and description of tail tips was based on non-genotyped specimens of Gosner stage 25.

Morphology. Long slender tadpole with narrow and long muscular tail; body depressed in lateral and elliptical in dorsal view ( Fig. 10 a, b); body length 28.3 ± 0.6% (N= 4) of total length; body height 43.1–43.9.0% (N= 2) of body length; body width 52.9–55.3% (N= 2) of body length; maximum body width on level of spiracle insertion; snout truncate in dorsal view; nostrils oval, situated laterally; nostrils equidistant from eye and snout tip; eye diameter 11.1–11.4% (N= 2) of body length; inter-orbital distance almost equals inter-nostril distance; tail fins narrow; dorsal fin originates distinctly posterior to the tail base, broader than ventral fin, reaching deepest point in last third of tail; ventral fin narrow, originates at level of tail base, runs almost parallel to tail axis, deepest point close to tail tip ( Channing et al. 2012 illustrate the tadpole with a very narrow dorsal fin, originating at about 25% of the tail, the ventral fin being distinctly deeper than the dorsal one); tail tip pointed to rounded; tail axis broad, converges in last third towards tail tip; vent tube dextral; lateral sacs present, extending from spiracle to end of body, covering lower two thirds of flanks; short sinister spiracle, translucent, opening lateral, not visible in dorsal view, originating slightly posterior to mid-body; mouth opening frontal; labial tooth row formula 0/0; both jaw sheaths completely keratinized, serrated and with a lateral pair of caniniform projections (fangs); median part of lower jaw with six to seven needle-like cusps ( Fig. 10 d); one distinct serration abaxial to fangs; upper jaw sheath narrow and almost straight; lower jaw sheath heavier, slightly bent, serration more pronounced; semicircular to bilobate posterior lip, covered with 20 large papillae ( Channing et al. 2012: 18) and numerous small papillae; arrangement of large papillae symmetric along vertical body axis, arranged in two semicircular rows; small papillae arranged along edge of posterior lip ( Fig. 10 c); short, straight to depressed w-shaped skin fold on lower lip, just posterior to lower jaw sheath; oral disc width 41.8 ± 7.1% (N= 4) of body length; mouth width 24.5 ± 4.6% (N= 4) of oral disc width.

The largest known individual (ZMB 78534, Gosner stage 25) measured 51.3 mm (body length. 14.3 mm; tail length: 37.0 mm). The most developed tadpole had a body length of 13.4 mm (ZMB 78540, Gosner stage 37, tail incomplete). Amiet (1980) reports a juvenile with 17 mm body length, still having a 10 mm tail.

Coloration in preservation. Dark brown body and tail, densely and irregularly mottled with dark brown spots; some individuals lighter colored; venter slightly lighter; tail fins mottled, dorsal one brownish with dark spots, ventral fin translucent with few spots.

Figures

FIGURE 10. Dorsal (a) and lateral view (b) of Leptodactylodon ovatus orientalis, fin tips added from morphologically corresponding individuals, with sketches of mouthpart (c; funnel mouth folded) in frontal view and jaw sheaths with caniniform projections in upper and lower jaw (d); scale bars: 1 mm.