Scotobleps gabonicus Boulenger, 1900

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 : 149-150

Scotobleps gabonicus Boulenger, 1900

Material examined.

ZMB 82118 and ZMB 82118A, both tadpoles Gosner stage 25, Cameroon, Ebo Forest, Ndogbanguengue, 113 m, 4°24'36.54"N, 10°10'10.19"E, 22 September 2012, leg. M. Dahmen; ZMB 88347 (GenBank MK318895), Gosner stage 41, Cameroon, near Korup National Park, Mokango, 5°8'2.26"N, 9°5'17.02"E, 8 May 2014, leg. F. Mühlberger; ZMB 88348 (GenBank MK318896), Gosner stage 25, Cameroon, near Korup National Park, Mokango, 758 m, 5°8'40.46"N, 9°5'6.70"E, 9 May 2014, leg. F. Mühlberger; ZMB 88349 (GenBank MK318897), Gosner stage 39, Cameroon, near Korup National Park, Mokango, 533 m, 5°7'50.1"N, 9°3'46.4"E, 10 May 2014, leg. F. Mühlberger; ZMB 88350 (GenBank MK318898), Gosner stage 25, Cameroon, Korup National Park, Esukatan, 189 m, 5°23'8.54"N, 9°0'36.72"E, 19 May 2014, leg. F. Mühlberger; ZMB 88354 (GenBank MK318899), Gosner stage 25, Cameroon, Korup National Park, Bera, 298 m, 5°21'5.47"N, 8°59'12.27"E, 23 May 2014, leg. F. Mühlberger; ZMB 88355 (GenBank MK318900), Gosner stage 35, ZMB 88356 (GenBank MK318901), Gosner stage 38, Cameroon, near Korup National Park, Ikundukundu, 147 m, 5°2'25.1"N, 8°55'3"E, 1 June 2014, leg. F. Mühlberger; ZMB 88357 (GenBank MK318902), Gosner stage 25, Cameroon, Korup National Park, Ikenge, 292 m, 5°16'30.86"N, 9°6'47.28"E, 13 May 2014, leg. F. Mühlberger.

All tadpoles were caught in small to medium-sized streams and rivers in low- to middle-altitude forests. The description is mainly based on ZMB 88355. The genotyped tadpoles have been compared with an adult from Big Massaka, Cameroon (MHNG 2716.24; GenBank MK318903). The uncorrected pairwise p difference between tadpoles and between tadpoles and the adult ranged from 0-0.4% (0-2 bp).

Description.

Long slender tadpole with slim, muscular tail (Fig. 18); body egg-shaped in dorsal view, slightly flattened in lateral view; snout rounded in dorsal view, more narrow-rounded and sloping in lateral view; body length 32.6 ± 1.0% of total length; body height 40.0 ± 5.9% of body length; body width 56.1 ± 3.4% of body length; eyes positioned dorsolaterally, eye diameter 11.7 ± 1.2% of body length; nostrils positioned dorsolaterally, closer to snout tip than to eyes; inter-nostril distance 59.5 ± 10.2% of interorbital distance; tail fins narrow, dorsal and ven tral fin originating from tail base, ventral fin height 64.5 ± 5.9%, of dorsal fin height; highest part of tail approximately in the middle of the tail; body height 87.9 ± 11.2% of maximum tail height; tail axis width 41.5 ± 7.2% of body width; tail axis height 68.5 ± 10.1% of maximum tail height; tail tip pointed; vent tube dextral; body with large lateral sacs, reaching from spiracle to end of body; short spiracle, sinistral; mouth ventral, near snout and smaller than interorbital distance; labial tooth formula 1:2/2:2; anterior lip carries no marginal papillae, posterior lip carries 2 or 3 rows of around 20-30 variable papillae, small lobe on each corner of the mouth (Fig. 18c), large rostral gap, papillae short and triangular (with rounded tip), marginal papillae bigger than those of inner row; jaws massive, black and fully keratinized; both jaws sharply serrated, upper jaw almost rectangular with 2 or 3 enlarged fangs on each side, lower jaw V-shaped without a notch.

The largest tadpole (ZMB 88347, Gosner stage 41) measured 62.2 mm. The tadpoles of Gosner stages 38 and 39 all measured about 60 mm total length.

Coloration in preservation.

Body brown, lateral sacs slightly more grayish; tail uniform dark brown at tail base, slightly fading to a fine but dense pattern of lighter brown speckles towards tail tip; fins yellowish brown with a dark reddish brown pattern.