Comprehensive DescriptionRead full entry
A small ranid frog with a pointed snout. Skin invariably warty, particularly on the back. SVL of adult males 14–16 mm, weight 0.31–0.41 g. adult females measure 17–19 mm and weight 0.51–0.72 g. The mean index head width/SVL is 0.28 (s.d. ± 0.03; 0.24–0.31; N = 7). The warts surrounding the center of the back are particularly prominent. Males have a single subgular vocal sac. When inactive, it just forms a slightly prominent elongate area (gular flap) whose edges converge towards the mouth. During the breeding season, nuptial pads develop on the thumbs of males. No eyelid cornicle. Tympanum indistinct. Hands without webs. Tips of fingers and toes at best slightly enlarged, without forming disks. Only residual webbing on the feet. A small inner metatarsal tubercle and a tarsal tubercle are present. Guibé & Lamotte (1963) give up to 21 mm (SVL) for females.
Voucher specimens: SMNS 8958 1–7.
Numerous dark patches, or patches with black borders, are scattered on the beige to dark yellow back, especially in the vicinity of the larger warts. Well-defined dark transversal bars are present on the thighs, shanks, lower arm, upper and lower lips. A yellowish to red vertebral line or band often runs from the eyes to the vent. If bands are present, their borders are usually less sharp than those of P. latifrons. The warts often are dark. The temporal triangle does not pass over into the lateral band; the latter only begins behind a light area above the arm. A smaller black triangle is found in the groin area; it sometimes stretches a short distance towards the back. The interval between these dark patches is light colored or even white. The lower edges of the posterior part of the thighs bear broad yellow longitudinal lines, which are bordered black. The latter neither turn upward in the vent region nor do they fuse above the anus. The distal part of the throat in males is always black. A few females have similarly colored throats. However, most of them have dark throats which are marked with more or less regular white spots. Otherwise, the throat, and the rest of the venter are white. A light interorbital line is often visible on animals preserved in alcohol. Otherwise, the frogs are either as contrasty as when they were alive, or they turn altogether beige to brown so that only the dark bars on the extremities remain clearly visible. In alcohol, the large warts are hardly ever as prominent as in life, but they remain visible, with some rare exceptions. The gular folds of the males may become indistinct.
The buzzing advertisement call lasts 3.6–4.0 sec and starts with very rapid pulses which are separated by ever longer pauses after 2.5 sec. They finally form groups comprising 4–7 pulses. These groups are separated by intervals of 0.02–0.08 sec. The frequency of the call ranges from 1.30–2.18 kHz.
The calls published by Schiøtz (1964c) basically show an identical structure, but their maximal intensity is much higher (4 kHz). With a call duration of only 0.3 sec, they are much shorter than the calls of the Comoé frogs.
So far, clutches of this species have not yet been identified with certainty. Most probably, they resemble those of P. latifrons. Small egg films, composed of lighter eggs are likely to be those of P. gutturosus. One of these films comprised 115 eggs (average diameter including jelly: 2.5–3.3 mm; egg: 0.86–0.90 mm). At Lamto, females contained 512 ± 144 eggs (N = 22; egg: 0.8 mm; Barbault 1984).
The tadpoles have not been definitely identified so far. If the above-mentioned eggs should have been produced by this species, the P. gutturosus larva does not differ from that of P. latifrons at all. A tadpole metamorphosed with five weeks The froglet measured 2.4 mm. being considerably smaller than all other metamorphosed frogs observed so far in the Comoé National Park. However, the size of other freshly metamorphosed P. gutturosus I found at forest ponds ranged from 6 to 8 mm. They weighed about 0.03-0.05 g.
This account was taken from Rödel, M.-O. (2000), Herpetofauna of West Africa vol. I. Amphibians of the West African Savanna, with kind permission from Edition Chimaira publishers, Frankfurt am Main.
For references in the text, see here