Phrynobatrachus fraterculus (Chabanaud, 1921)
This species is named for the Latin 'fraterculus' meaning little brother.
Phrynobatrachus fraterculus is a small sized species (SVL < 25 mm) of puddle frog known from Sierra Leone, Guinea, Liberia and Côte d'Ivoire. 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 an indistinct tympanum, digit tips expanded into small discs, and absence of pedal webbing. A brown-black band, bordered by white, extends from snout tip, through the eye and tympanum and along the lateral side of the body to the insertion of the thigh. The ventral surface is white with scattered spots. Males exhibit nuptial pads on manual digit I, ovoid femoral glands, a slate grey throat (medium brown after preservation) and gular folds that form a U-shaped pouch.
The IUCN Red List (2009) categorizes this species as Least Concern in view of its relatively wide distribution, its presumed large population, and because it is unlikely to be declining fast enough to qualify for listing in a more threatened category (Rödel and Schiøtz, 2004).
It occurs in Taï National Park and Mount Nimba World Heritage Site (Rödel and Schiøtz, 2004).
It is affected by the loss of forest habitat for agriculture, logging, human settlements, and mining (Rödel and Schiøtz, 2004).
Populations of this species are decreasing (Rödel and Schiøtz, 2004).
This small-sized species (SVL of males up to 19 mm; females up to 25 mm) is characterized by an indistinct tympanum, digit tips expanded into small discs, and absence of pedal webbing. A brown-black band, bordered by white, extends from snout tip, through the eye and tympanum and along the lateral side of the body to the insertion of the thigh. Brown-black spots, also bordered by white, are present in the inguinal region. The ventral surface is white with scattered spots. Males exhibit nuptial pads on manual digit I, ovoid femoral glands, a slate grey throat (medium brown after preservation) and gular folds that form a U-shaped pouch .
Mitochodrial sequence data from 12S rRNA, valine-tRNA, and 16S rRNA fragment, as well as combined sequence data from mitochondrial and nuclear (RAG-1) genes indicate that P. fraterculus is the sister species to P. maculiventris and three possible new species: P. sp. nov 3 from Guinea, P. aff. gutturosus 1 from Côte d’Ivoire, and P. aff. gutturosus 2 from Côte d’Ivoire (Zimkus, 2010)
Phrynobatrachus fraterculus differs from several small West African puddle frogs (P. annulatus, P. calcaratus, P. taiensis, P. villiersi) by the absence of an eyelid cornicle. It differs from P. francisci, P. intermedius, P. plicatus, P. liberiensis, P. natalensis,and P. latifrons (= P. accraensis, Frétey 2008) by its much less developed webbing (Guibé & Lamotte, 1963; Rödel et al., 2009). It may be confused with P. maculiventris, with which it shares the almost completely smooth dorsal skin and large femoral glands in males (Barbour and Loveridge, 1927; Parker, 1936; Blackburn, 2005; Rödel et al., 2009). P. fraterculus can be differentiated from P. maculiventris by its complete white upper lip, compared to white spots on a brown upper lip in P. maculiventris. A distinct ventral pattern in also present in P. maculiventris with large irregularly shaped dark brown blotches separated by thin white lines.
This is a small, stout-limbed species with a moderately pointed snout and almost completely smooth dorsal skin. The nostril is nearer to the tip of the snout than the eye with its distance from the eye less than half of the ocular diameter. Upper eyelid width is almost equal to interorbital distance. The tympanum is indistinct. Manual webbing is absent. The tarsal tubercle is small, white, and located on the ventromedial surface near the middle of the tarsus, but closer to the metatarsal tubercles. An outer metatarsal and slightly larger and ovular inner metatarsal tubercle are present. Finger and toe tips are expanded into discs, with lateral and slight distal expansion of the dorsal surface. Webbing between toes is absent with 4 phalanges free on toe IV. Four inconspicuous, flat glands are present on the smooth and shiny dorsal surface. The first pair of glands form a V shape, and the second pair are larger and directed in the opposite direction. Males exhibit elongate, ovoid femoral gland on the posterior femur. The thumb of reproductive males is swollen at base and on medial surface of hand, extending complete white upper lip onto the dorsal surface.
The dorsum is grayish brown, and a thin, white vertebral line may be present. A conspicuous brown-black band extends from snout tip, through the eye and tympanum and along the lateral side of the body to the insertion of the thigh. A white band borders this thick band both anteriorly and posteriorly, although the posterior band is significantly thicker. Brown-black spots are present in the inguinal region and are bordered by white. The dorsal surface of femur is brown and separated into anterior and posterior sections by a white band running that begins at the vents and continues to the ventrolateral surface of the knee. The ventral surface is white with scattered spots. No distinct bar is present on the femur; one medium brown bar on tibia-fibula is incipient or absent. The upper lip is completely white. The throat is dark slate grey (medium brown after preservation). Males exhibit two lateral gular folds and a prominent posterior gular fold, forming a U-shaped pouch for the vocal sac.
Snout-vent length up to 19 mm in males and 25 mm in females (N= 153; Guibé and Lamotte, 1963). Rödel and Ernst (2002) reported that males ranged from 17.1-19.0 mm (N=4), while a single female measured 25 mm.
This species occurs in central and eastern Sierra Leone, southern Guinea, Liberia and western Côte d’Ivoire. Records from Guinea-Bissau require confirmation (Rödel and Schiøtz, 2004).
It is a rainforest species, where it is generally found close to small streams in leaf-litter. It can survive in secondary forest and plantations, but not in open areas. It probably occurs up to at least 1,000m asl, perhaps higher (Rödel and Schiøtz, 2004).
It is very common in Guinea, but it is very rare in Taï National Park in Côte d’Ivoire (Rödel and Schiøtz, 2004).
Call published by Schiøtz (1964).