Astylosternus batesi

Description. Long slender tadpole with long, muscular tail and narrow fins (Fig. 1); body oblong oval in dorsal and lateral view; back with a medial longitudinal-depression; snout rounded in dorsal view, more narrow-rounded in lateral view; body length approximately 0.3 (31.3 - 36.7 %, N = 3) of total length; body height 46.3 + / - 5.6 % of body length; body width 60.5 + / - 6.0 % of body length; eyes positioned dorsolaterally, eye diameter 11.3 + / - 1.4 % of body length; nostrils positioned dorsolaterally, closer to snout tip than to eyes; inter-nostril distance 75.2 + / - 9.7 % of interorbital distance; tail fins narrow, dorsal and ventral fin originating from tail base, ventral fin height narrow, reaching 70.7 + / - 4.7 % of dorsal fin height; highest part of tail approximately in the middle of the tail; body height 91.7 + / - 11.5 % of maximum tail height; tail axis width 41.3 + / - 11.4 % of body width; tail axis height 59.8 + / - 13.9 % of maximum tail height; tail tip rounded; vent tube dextral; body with large lateral air sacs, extending from spiracle to end of body; short spiracle, sinistral; mouth ventral, very close to snout, narrower than interorbital distance; keratodont formula 1: 2 / 2 + 2: 1; anterior lip only lateral with papillae, large rostral gap; posterior lip with 2 - 3 rows of approximately 20 uniform papillae, papillae triangular and approximately as long as broad (Fig. 1 d); black jaw sheaths massive and serrated; upper jaw with a big medial projection (fang); lower jaw U-shaped with a medial notch. The largest tadpole, still Gosner stage 25 (ZMB 82865), measured 25 mm body length. The most developed specimen (ZMB 82784, Gosner stage 36) had similar body length of 24.7 mm. When reconstructing the tail tip of the largest specimens by the shape of tails in smaller specimens we estimate the maximum total length of A. batesi tadpoles to be 60 - 80 mm.

Material examined. ZMB 82863 (GenBank MK 318840), Gosner stage 25, Cameroon, Mt Kala, 899 m, 3 ° 50 ' 27.66 " N, 11 ° 20 ' 52.44 " E, 9 November 2011, leg. M. F. Barej, H. C. Liedtke & N. L. Gonwouo; ZMB 82864 (GenBank MK 318841), Gosner stage 25, Cameroon, Ebo Forest, Bekob, 893 m, 4 ° 21 ' 51.96 " N, 10 ° 25 ' 10.26 " E, 30 September 2011, leg. M. Dahmen; ZMB 82865 (GenBank MK 318842), Gosner stage 25, Cameroon, Ebo Forest, Bekob, 852 m, 4 ° 21 ' 54.36 " N, 10 ° 25 ' 17.22 " E, 1 September 2011, leg. M. Dahmen; ZMB 82866 (GenBank MK 318843), 2 tadpoles, Gosner stage 25, Cameroon, Ebo Forest, Bekob, 917 m, 4 ° 21 ' 27.42 " N, 10 ° 25 ' 5.94 " E, 9 January 2011, leg. M. Hirschfeld & F. Groezinger; ZMB 82784 (GenBank MK 318844), Gosner stage 36, Cameroon, Ebo Forest, Bekob, 807 m, 4 ° 21 ' 54.3 " N, 10 ° 25 ' 24.54 " E, 10 January 2011, leg. M. Hirschfeld & F. Groezinger. All tadpoles were caught in small to medium-sized streams. The description is mainly based on ZMB 82865 and ZMB 82784. Genotyped tadpoles have been compared with an adult frog (MC 11 _ 205; GenBank MK 318905) from Mount Kala, near Kala village, Cameroon. The genotyped individuals were genetically almost identical, the maximum uncorrected p-differences in pairwise comparisons was 0.2 % (1 bp).