Ahl's River Frog

general

The two populations of puddle frogs identified as P. aff. latifrons from the Democratic Republic of Congo and Tanzania are morphologically similar to the West African P. latifrons but differ from this species by 18–19% in mtDNA (Zimkus et al., 2010). In addition, the P. aff. latifrons populations differ from each other by 7–8%. Additional study is needed to determine if these species can be assigned to known species or if this group comprises one or two new species.

African Amphibians

general

This species is named for the Latin 'latus' meaning wide or broad and 'frons' meaning forehead, brow, or face.

African Amphibians

morphology

This species has a rather pointed snout, and the skin is smooth with a number of large and rounded warts on the dorsum, particularly on the anterior part of the back, and central outer parts of thighs. Additional large comma-shaped warts converging towards the snout are found behind the eyes. The mean index head width/SVL is 0.26 ± 0.03 (N = 57). The tympanum is visible but very small and feebly defined. No eyelid cornicle is present. The tips of fingers and toes may be slightly enlarged, but digital discs are not present. Manual webbing is absent, and rudimentary webbing is present on the feet with 2-2.5 phalanges free on toe IV. The pedal webbing formula is: 1 (0) or (0.5); 2 i/e (1–0) or (0.75–0.5) or (0.5–0); 3 i/e (1) or (1–0.5); 4 i/e(2) or (1.5); 5 (0.5) or (1). A small inner metatarsal tubercle, an outer metatarsal tubercle, and a tarsal tubercle are present. Males have a subgular vocal sac that is not always clearly discernible. The basic color of the dorsum varies from light gray brown, or darker brown to almost black. Almost black animals are found on darker soil, whereas those encountered on lighter substrates are beige. Breeding males may be bright yellow or green. P

African Amphibians

behaviour

During the dry season, P. latifrons lives on the riverbanks and near those forest ponds that still contain water. The frogs inhabiting forests, particularly the humid tracks of large mammals, are diurnal, while those living on the riverbanks are strictly nocturnal. During the day, these frogs seek refuge under stones and dead wood or in crevices on the very edges of water bodies where the temperature may be 35 °C at most, compared to 40 °C outside these refuges. At night, the frogs forage for prey in a very limited area bordering open water, feeding mainly on arthropods. Some individuals always seem to hunt in the same area. Complexly structured bank sectors usually harbor more frogs. Habitat choice and activity period are apparently humidity dependent (Rödel ,1995). After rainfall, many individuals leave the river area, cross the gallery forest, and arrive at the savanna ponds recently filled with water. This “migration” or habitat shift may be a result of many factors. First, rising water level of the river may directly threaten the frogs. Second, the soil is much more humid after rain, and these frogs may therefore not be restricted to foraging at the edge of the river. Lastl

African Amphibians