AMPHIBIAWEB
Phrynobatrachus africanus
family: Phrynobatrachidae

© 2009 Dr. Peter Janzen (1 of 6)

  hear Fonozoo call

Conservation Status (definitions)
IUCN (Red List) Status Least Concern (LC)
CITES
Other International Status None
National Status None
Regional Status None

Country distribution from AmphibiaWeb's database: Cameroon, Central African Republic, Congo, Gabon

 

View distribution map using BerkeleyMapper.

   

From the Encyclopedia of Life account:

Etymology

This species name is from the Latin 'africanus,' meaning African or of Africa.


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/

Summary

Phrynobatrachus africanus is a medium sized species (SVL < 31 mm) of puddle frog known from Cameroon, Equatorial Guinea (including the island of Bioko), Gabon, Congo, and the Central African Republic. Members of this genus are identified by the presence of a midtarsal tubercle, elongate inner metatarsal tubercle, and outer metatarsal tubercle. This species is characterized by a distinct tympanum, tips of fingers and toes dilated into small discs, and moderate pedal webbing. Males have dark throats, lateral vocal folds, and enlarged pseudo-teeth in the lower jaw.


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/

Distribution

This species is known from western, central and southern Cameroon, Equatorial Guinea (including the island of Bioko), Gabon, southern Congo, and southwestern Central African Republic (Amiet et al, 2004). It might occur also in southeastern Nigeria, the Cabinda Enclave of Angola, and extreme western Democratic Republic of Congo.


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/

Morphology

Tongue with a conical papilla in the middle. Habit is moderately slender. The head is approximately as broad as long, triangular in shape, rounded in front, and depressed above. Eyes are of moderate size. Interorbital space is as broad as the upper eyelid. Canthus rostralis is distinct, and the loreal region is concave. Nostril is equidistant from from the eye and the snout tip. Tympanum is distinct, measuring 3/5 the diameter of the eye, and is situated over the angle of the jaw. Posterior nares are suboval and small. The fingers lack webbing. The first and second fingers are of approximately equal length, although first finger may not extend as far as the second. The fourth is longer than these, and the third is the longest. The subarticular tubercles are distinct. Tips of fingers and toes dilated into small discs. Toes I and II are nearly in line with each other. Toe II is longer than toe II, toe IV is the longest, and toe V is longer than I and II. Pedal webbing extends to the middle of the antepenultimate phalanx. Zimkus (unpublished) found that webbing was moderate with 3-3.5 phalanges free on toe IV. An ovular inner metatarsal tubercle and a small, round outer metatarsal tubercle are present. Although Drewes and Perret (2000) found this species to lack a tarsal tubercle, Zimkus and Blackburn (2008) found the tarsal tubercle present, albeit rather reduced in size. A tarsal tubercle was neither mention in the original description of this species by Hallowell (1868) nor the description of P. latirostris by Boulenger (1900), which was later synonymized, but it was mentioned in the description of Arthroleptis africanus, also by Boulenger (1900). The tibio-tarsal articulation reaches between the eye and the end of the snout. There is a slightly curved fold behind the eye, converging towards its fellow on the scapular region. According to Hallowell (1868) and Boulenger (1900; P. latirostris), the dorsum and abdomen are smooth, while Boulenger (1900; A. africanus) notes small, flat warts. Femoral glands are absent (Böhme; 1994). Prominent nuptial pads on manual digit I and lateral vocal folds are present in males (Zimkus and Blackburn, 2008). Böhme (1994) states that enlarged “teeth” are present in the lower jaw followed by smaller mandibular teeth in both sexes; Noble (1931) reported that the ‘‘teeth’’ in this species are the hypertrophied margins of the prearticular bone. Scott (2005) did not consider these structures to be homologous with mandibular odontoids (sensu Fabrezi and Emerson, 2003) and suggested that these tooth-like tusks are used in male combat.

Dorsum is brown or greyish. The body appears to be blotched all over with dark brown on a much lighter brown when examined when magnified. A dark triangular spot may be present between the eyes. Glandular folds are edged with a slightly darker color. Upper jaw exhibits several chocolate colored spots or vertical bars upon a lighter ground. Lower lip brown in males, with a series of small white spots. Posterior extremities barred with bark brown approaching a black. Anal region is blackish, edged with whitish above. Belly and lower surface of the limbs are white, breast spotted with brown. Throat is dark grey in the male, spotted with brown in the female (Hallowell, 1868; Boulenger, 1900).


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/

Size

The holotype measured approximately 25.4 mm (1 inch; Hallowell, 1858). Boulenger (1900) notes that Phrynobatrachus latirostris and Arthroleptis africanus, both later synonymized with P. africanus, measured 30 mm. Zimkus (unpublished) examined specimens that measured from 17.8-30.4 mm in SVL (N=5).


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/

Diagnostic Description

This species is characterized by a distinct tympanum, tips of fingers and toes dilated into small discs, and moderate pedal webbing. Males have dark throats, lateral vocal folds, and enlarged “teeth” in the lower jaw.


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/

Comparisons

The presence of enlarged “teeth” the lower jaw makes males of this species easily identifiable. The only other species of Phrynobatrachus that exhibits mandibular pseudo-teeth is Phrynobatrachus sandersoni, which exhibits greatly enlarged T-shaped digital discs.


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/

Habitat and Ecology

It is a lowland forest species that can survive in somewhat degraded forest, but not in open habitats outside forest (Amiet et al, 2004).


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/

Population Biology

It is a very common species (Amiet et al, 2004).


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/

Advertisement Call

Márquez et al. (2000) described the call as a short trill (346-384 ms.) that is rather irregular (T/P is highly variable). The mean dominant frequency is at 2614 Hz, but the emphasized frequency range is wide. The call has a fast raise time and a longer fall time.


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/

Reproduction

The males call from cavities and holes near streams, and it breeds in still water pools along streams (Amiet et al, 2004). Márquez et al. (2000) reported that males call continuously during the day, throughout the year, from the banks of streams and rivers in the forest.


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/

Phylogenetics

Mitochodrial sequence data from mitochondrial 12S rRNA, valine-tRNA, and 16S rRNA , as well as combined sequence data from mitochondrial and nuclear (RAG-1) genes support a sister relationship between P. africanus and a monophyletic clade of species that includes all highland (submontane and montane) Cameroonian and Nigerian taxa (Zimkus, 2009; ZImkus et al, 2010). This group includes P. chukuchuku, P. cricogaster, P. manengoubensis, P. steindachneri, P. werneri, and one lowland species, P. batesii.


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/

IUCN Red List Category and Justification of Conservation Status

The IUCN Red List (2009) categorizes this species as Least Concern in view of its wide distribution, tolerance of a degree of habitat modification, presumed large population, and because it is unlikely to be declining fast enough to qualify for listing in a more threatened category (Amiet et al., 2004).


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/

Trends

Populations of this species are decreasing (Amiet et al, 2004).


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/

Threats

Despite its adaptability, it is likely to be affected by forest loss due to logging, agricultural encroachment and human settlement (Amiet et al., 2004).


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/

Conservation Actions and Management

It occurs in several protected areas, including Korup National Park in Cameroon, Monte Alen National Park in Equatorial Guinea, Moukalaba-Dougoua Faunal Reserve in Gabon, and Dzanga-Ndoki National Park in Central African Republic (Amiet et al., 2004).


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/