Comprehensive DescriptionRead full entry
A typical large and compact toad with a warty skin. SVL of adult males 62-91 mm, females 70-130 mm. Large prominent kidney-shaped or parallel parotid glands, with a relatively smooth appearance because the warts are quite flat in this region. The large tympanum reaches 0.7 to, occasionally, 1.5 of the eye diameter. The tympanum shows a shallow circular depression. Therefore one might get the impression of a ring surrounding the ear. Males have a single subgular vocal sac, enlarged thenar tubercles and black nuptial pads on the outer faces of the first and second fingers, the latter are often less well-defined. The horny tips of the warts are apparently more pointed on males. However, these horny asperities are usually flat. The hind limbs have traces of webbing. The inner metatarsal tubercle reaches 0.5-1 of the length of the shortest toe. These toads have only few subdigital tubercles, which are less conspicuous in older specimens than in adult B. maculatus.
According to Inger & Greenberg (1956), male B. regularis have most often a single, sometimes paired, lateral slit in the floor of the mouth that forms the connection to the median, subgular vocal sac. Nuptial pads of breeding B. regularis males consist of densely pigmented clusters of asperities on the first, second, and third fingers and on the median part of the inner palmar tubercle.
Voucher specimens: SMNS 8947 1-3; SMF 78623; SMNS 8988, Ananda, Ivory Coast.
Coloration: Dark olive brown basic dorsal color, often turning lighter towards the venter. The skin between the tiny warts on the flanks often appears almost black. This toad also contains numerous dark patches on the upper lip, on the eyelids, and on the dorsal parts of the extremities. On the back, these dark patches are often arranged more or less symmetrically. The body axis is often highlighted by a light vertebral stripe which appears rather distinct on young animals but usually fades when they mature, turning to the same color as the back. Often pale patches are present on the back, too. The venter is uniform white to beige, the throat of males is black. According to Tandy et al. (1985), some animals also show dark markings on their venter. Preserved animals usually do not show any change of color. However, specimens tend to fade as time goes by.
Voice: A lengthy rattling sound, lasting 0.9 sec and composed of two elements which are repeated continuously. The initial element comprises numerous pulses (0.01 sec) separated by pauses (0.02 sec) and lasts about 0.4 sec. After a pause of 0.05 sec, the second element follows, lasting 0.5 sec. As the former, it is made up of pulses of 0.01 sec, but these are separated by longer pauses of 0.03 sec.
According to Tandy et al. (1985), the calls vary considerably depending on temperature and the animals size. These authors give a frequency of 0.3 to 2.5 kHz. The dominant frequency of the advertisement call in Ethiopian B. regularis is 0.5-1.6 kHz (Tandy et al. 1982). The calls published by Amiet (1976a) are similar to those of the Comoé toads. The calls of Serengeti toads published by Wickler & Seibt (1974) and assigned to B. regularis by them, are supposed to be those of B. gutturalis (Van Den Elzen & Kreulen 1979). The call published by Schiøtz (1964c) is most probably that of B. maculatus.
Noble (1924) reported that female toads were answering the male call "wook-wook" with a sound like "woop" followed by a quick "wop-wop". However, it is not sure if that observation was really on B. regularis, e.g. they describe the vocal sac of the male as reaching twice the size of the head, and being bluish in color.
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.
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