Werneria submontana

Rödel, Mark-Oliver, Schmitz, Andreas, Pauwels, Olivier S. G. & Böhme, Wolfgang, 2004, Revision of the genus Werneria Poche, 1903, including the descriptions of two new species from Cameroon and Gabon (Amphibia: Anura: Bufonidae), Zootaxa 720, pp. 1-28 : 17-20

Werneria submontana nov. sp.

Figs. 1 d, 2d, 3d, 4d, 8b, 10a

Holotype.— ZFMK 69699, adult male, Bakossi Mts., Edib Hills, Lake Edib, N 4°57’, E 9°39’, 1,100 m a.s.l., Cameroon, 5.–7.V.1998, C. Wild.

Paratypes.— ZFMK 67271, juvenile, 1,250 m a.s.l., 14.I.1998, O. Euskirchen, other data as holotype; ZFMK 69747, adult male, same data as holotype; ZFMK 69698, 69700, adult female and male, Bakossi Mts., Edib Hills, Elabah Camp, 1,100 m a.s.l., Cameroon, 5.–7.V.1998, C. Wild; ZFMK 67272, 67781­785, six juveniles, Bakossi Mts., Mwendelengo Mts., Kodmin, 1,070 m a.s.l., Cameroon, 18.–25.XII.1997 & 24.I.1998, O. Euskirchen & A. Schmitz; ZFMK 67786, adult male, Meked, Cameroon, 8.–10.I.1998, A. Schmitz; ZFMK 67787­796, ten juveniles, Mt. Kupe, south­west side (north­west flank in catalogue of ZFMK), Nyasoso, 910 m a.s.l., Cameroon, 18.–25.XII.1997, A. Schmitz.

Diagnosis.— A medium­sized, slender but compact Werneria with short and rounded snout; skin of flanks and throat wrinkled, at least in adult males, otherwise skin smooth; a distinct, broad white, yellowish or reddish dorsolateral line occurs on the dark brown dorsum; urostyle bordered by a pair of longitudinal black lines; lower flanks with large clear spots; greyish venter with large clear spots, toes nearly fully webbed. Superficially this species is most similar to W. mertensiana , W. preussi and the new Gabonese species (see below). From the Gabonese species and W. bambutensis , W. submontana nov. sp. differs by its less­developed webbing and from W. tandyi , W. mertensiana and W. preussi by its more extensive webbing. It differs from the Gabonese species by a different body shape and much broader dorsolateral lines. With W. mertensiana it shares the black bars on hind legs and the black borders of the urostyle, but differs by its wrinkled flanks that bear clear spots on the ventral part, the more distinctly dorsal border of the dorsolateral lines and head shape. From W. preussi it differs by its dorsal and ventral coloration. It differs from all Werneria species by the wrinkled skin on throat (at least in adult males).

Description of the holotype.— The holotype is an adult male with slender but compact body shape ( Fig. 1 d); 35.4 mm SVL; short, broad but rounded snout; head width 11.3 mm, eye diameter 4.0 mm; interorbital distance 4.6 mm; naris closer to snout tip (2.4 mm) than to eye (3.1 mm); small warts at angle of mouth ( Fig. 4 d), skin of back and venter smooth; broad (2 mm at mid­body) white dorsolateral lines that extend from snout to groins; dorsolateral line distinctly separated from back and flank coloration and broadened posteriorly; back dark grey; blackish flanks with granular skin, lower flanks with white spots; back uniform dark brown to black; urostyle bordered by black lines; dorsal surfaces of extremities dark brown with two black bars on thighs, lower leg and feet ( Fig. 1 d); basic colour of venter brownish grey; posterior venter with large (> 4 mm) yellowish spots; breast and throat grey with a dark ventral figure on throat and few smaller yellowish spots; skin of throat wrinkled ( Figs. 2 d, 10a); ventral surfaces of thighs and lower leg reddish brown with large yellowish spots on the whole surface; long, but broad, hind legs, femur length 16.7 mm, tibia 17.2 mm, foot (incl. longest toe) 25.2 mm; toes 2, 3 and 5 completely webbed, tip of toe 1 and external side of toe 4 without web ( Fig. 3 d).

Variation and colour in life.— Adult males SVL ranged from 31.3–35.4 mm, the only adult female measured 44.5 mm. The smallest juvenile was 10.5 mm long. Other measurements of paratypes are summarized in Tables 1–3. Body dimensions and colouration generally were as in the holotype. Other adult males also had a wrinkled skin on throat. The female’s throat was only faintly wrinkled. Warts at angle of mouth may be difficult to see or absent. Juveniles generally differ from adults by having smooth skin on flanks and throat.

In life these toads have a golden iris; dorsal colour dark brown to black; pale, whitish, pink or orange­red dorsolateral stripes ( Fig. 8 b), very faint in the one adult female; upper part of flanks dark brown to black, lower part of flanks with yellowish spots that may be hard to see in juveniles; belly dark grey with numerous cream speckles; belly generally with larger spots than breast and throat, however, in some specimens not exceeding 1–2 mm in size; femur, tibia, foot brownish with two black bars on each; forefeet and fingers with yellowish spots.

Natural history.— W. submontana occurs in an altitudinal range of about 800–1,200 m a.s.l., occasionally it may be found at lower altitudes (see below). This species was found in broad daylight either under rocks in a partly dried up river basin (Kodmin; Fig. 11 b), or on stony ground between wet, very low vegetation which was lying in the spray area of a small, artificial waterfall (Mt. Kupe; Fig. 11 c). The habitat at the base of Mt. Kupe, where this species seem to live in sympatry with W. preussi (see above), was within a transition zone between good quality secondary forest, and more­or­less undisturbed primary forest at 910 m a.s.l. M. Gartshore (pers. comm.) found these toads near the same locality a little lower at 850 m a.s.l., under rocks during the day along a stream on the grounds of the Nyasoso Girls Secondary School, above the school reservoir, just outside town. The very wrinkled throat of adult males may indicate that this species utters an advertisement call.

Distribution.— Known from the Bakossi Mts., Mwendelengo Mts. and Nyasoso at the base of Mt. Kupe ( Fig. 5 ). Judging from pictures kindly provided by M. Gartshore, the 38 W. mertensiana specimens recorded by her in February and April in the streams around Nyasoso at 850 m on the western slope of Mt. Kupe ( Gartshore 1984) are W. submontana . Likewise a specimen collected by Amiet (1975, 1976b) in the vicinity of Nkongsamba (Maholé, 10 km north­west of Tombel, forest reserve of Bakossi, primary rainforest, 300– 350 m a.s.l.), may belong to this new species. W. submontana might also occur on the Rumpi Hills, as characters of three preserved specimens from Mofako showed characters that best fit this new species (photos provided by J.­L. Amiet).

Etymology.— The name submontana indicates the altitudinal range of this new species.

Figures

FIGURE 1: Dorsal view of Werneria species; a: W. iboundji nov. sp. female, holotype, IRSNB 1929; b: W. bambutensis male, MHNG 1453.17; c: W. tandyi male, MHNG 1453.21; d: W. submontana nov. sp. male, holotype, ZFMK 69699; e: W. mertensiana male, ZFMK 69137; f: W. preussi male, SMF 24180.

FIGURE 2: Ventral view of Werneria species; a: W. iboundji nov. sp. female, holotype, IRSNB 1929; b: W. bambutensis male, MHNG 1453.17; c: W. tandyi male, MHNG 1453.21; d: W. submontana nov. sp. male, holotype, ZFMK 69699; e: W. mertensiana male, ZFMK 69137; f: W. preussi male, SMF 24180.

FIGURE 3: Left hind feet of Werneria species, webs are stippled; a: W. iboundji nov. sp. female, holotype, IRSNB 1929; b: W. bambutensis male, MHNG 1453.17; c: W. tandyi male, MHNG 1453.21; d: W. submontana nov. sp. male, holotype, ZFMK 69699; e: W. mertensiana male, ZFMK 69137; f: W. preussi male, SMF 24180.

FIGURE 4: Heads of Werneria species, illustrating shape of snout, dorsolateral lines (stippled), warts and spines; a: W. iboundji nov. sp. female, holotype, IRSNB 1929; b: W. bambutensis male, MHNG 1453.17; c: W. tandyi male, MHNG 1453.21; d: W. submontana nov. sp. male, holotype, ZFMK 69699; e: W. mertensiana male, ZFMK 69137; f: W. preussi female SMF 24159; g: W. preussi male, SMF 24180.

FIGURE 5: Distribution of known Werneria species; compare with text.

FIGURE 8: a: W. preussi female from Buëa, Mt. Cameroon; b: W. submontana nov. sp. male, Bakossi Mts., Lake Edib; c: W. mertensiana male, Mt. Kupe (photo: K. ­ H. Jungfer); d: ventral view of Werneria sp., Monte Alén National Park, Equatorial Guinea (photo: I. de la Riva).

FIGURE 11: Habitats of Werneria submontana nov. sp. on the Bakossi Mts.; a: Edib Hills, surroundings of Lake Edib (type locality); b: small forest creek on Mwendelengo Mts., Kodmin, several of the paratypes have been collected beneath the stones on the creek’s bank; c: watercatchments at Mt. Kupe; the toads were living in the spray zone of the small, artificial waterfall.