Phrynobatrachus maculiventris Guibé and Lamotte, 1958
The name Cardioglossa liberiensis Barbour and Loveridge, 1927 had priority over Phrynobatrachus maculiventris Guibé & Lamotte, 1958; however, Phrynobatrachus liberiensis Barbour and Loveridge, 1927 was already in use for another widespread West African puddle frog species (Rödel et al., 2009). Interestingly, P. liberiensis was described in the same Barbour & Loveridge (1927) paper where they introduced Cardioglossa liberiensis. Consequently, the name P. maculiventris Guibé & Lamotte (1958) was used instead.
Phrynobatrachus maculiventris is a small to medium sized species (SVL < 26 mm) of puddle frog known from Liberia, Guinea, 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 it's elongate body, long hind legs, indistinct tympanum, and absent or rudimentary webbing. The ventral color pattern is distinct with large irregularly shaped dark brown blotches separated by network of fine white lines on the belly and large dark brown blotches on the ventral side of thighs, lower leg and foot. The flanks and also have a well delimitated black stripe, separated by a white line from a black spot in the groin area, and posterior surfaces of thigh have a longitudinal and well defined white line. Males have ovoid femoral glands, and the black and granular vocal sac is bordered laterally on each side by prominent folds. Their tadpoles are unmistakable due to their aposematic black and yellow colour pattern.
Phrynobatrachus maculiventris is not currently included in the IUCN's Red List assessment of amphibian species. However, P. maculiventris would be considered Vulnerable following the IUCN Red List categories and criteria because the extent of occurrence is less than 20,000 km2, the area of occupancy is much less than 2,000 km2, less than 10 localities are known, and these localities and the presumed preferred habitat in the area is declining (Rödel et al., 2009).
The preferred habitat of this species, primary rainforest, is continuously declining through logging, agricultural encroachment, and mining activities (Rödel et al., 2009).
A present and future population decline, by habitat loss and/or reduced habitat quality, can be inferred by the habitat degradation at the type locality and the ongoing prospecting activities for mining on Monts Nimba, the Diécké Forest Reserve and many other montane forest areas in south-eastern Guinea and Liberia (Rödel et al., 2009).
This species is characterized by its elongate body, long hind legs, indistinct tympanum, and absent or rudimentary webbing. The ventral color pattern is distinct with large irregularly shaped dark brown blotches separated by fine white lines on the belly and large dark brown blotches on the ventral side of thighs, lower leg and foot. The flanks and also have a well delimitated black stripe, separated by a white line from a black spot in the groin area, and the posterior surfaces of thigh have a longitudinal and well defined white line. Males have ovoid femoral glands, and the black and granular vocal sac is bordered laterally on each side by prominent folds.
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. maculiventris is the sister species of P. aff. gutturosus 2 from Côte d’Ivoire, most likely a new species (Zimkus, 2010).
The tadpoles of Phrynobatrachus maculiventris are easily assignable to the genus Phrynobatrachus by their body shape, the long filamentous papillae (that are however only comparatively few in number and particularly massive) and very small size at metamorphosis. However, they differ from all known congeners by their very peculiar, aposematic black and yellow dorsal pattern (Rödel et al., 2009)
Larvae are exotrophic are lotic. Body is ovoid in dorsal view, slightly depressed in lateral view. Body length approximately two times of body width. Comparatively large eyes are positioned dorsolaterally; nares are large, positioned dorsally, closer to tip of snout than to eyes. Oral disc is ventral. Dorsal lip wide and smooth; ventral lip with uniserial marginal papillae, the four median ones very long and filamentous. The upper jaw sheath is shaped as a depressed "m". The lower jaw sheath is u-shaped, and the jaw sheath edges are only pigmented towards the edges which are serrated. Labial tooth row formula is 1/1+1:1. Infra-angular labial teeth rows present on separate dermal lobes. Keratodonts are almost translucent, light brown, and thus hard to see. Vent is dextra and spiracle is sinistral. Tail length only slightly longer than body length. Tail axis height at its base is almost equal to maximum height of dorsal fin. The dorsal part of fin originates dorsal to tail-body junction, and the highest point is at mid-length of tail. The ventral part of fin is narrower than tail axis (musculature), almost parallel to tail axis. The tail tip is rounded. Dorsum is black, interrupted by three clear yellow transverse bands: the first on the snout, the other two at mid-body and at the posterior end of the body, respectively. The tail axis is yellowish with black bands. The ventral surfaces are light coloured, and the tail fin transparent. In preservative the colouration fades to light beige and brown. Judging from the oldest tadpole stages, juveniles most likely metamorphose with approximately 6.5-7.5 mm snout-vent length. The tadpole description is based on six specimens at Gosner stages 36-41 (ZMB 71594).
Phrynobatrachus maculiventris 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. It differs from all the above mentioned species plus P. batesii, P. brongersmai, P. ghanensis, P. guineensis, P. gutturosus, P. phyllophilus, P. pintoi, and P. tokba by the absence of dorsal warts or ridges. It may be confused with P. fraterculus, with which it shares the almost completely smooth dorsal skin and large femoral glands in males. 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, and the venter of P. fraterculus that has a few small black spots or is uniform clear, compared to the distinct ventral pattern in P. maculiventris with large irregularly shaped dark brown blotches separated by white lines.
A small Phrynobatrachus with elongate body, very long hind legs, and short pointed snout that is rounded in dorsal and lateral view. The canthus rostralis is rounded, and the loreal region slightly concave. The head-width directly behind the eyes is 0.3 times the snout-vent length (SVL); eye-snout distance is slightly larger than eye diameter. The nostril is closer to snout than to eye. The tympanum is present but indistinct with a diameter less than half of the eye. A short but distinct supratympanic fold is present, stretching from posterior edge of eye to the base of forearm. The femur is shorter than the tibio-fibulae and approximately half of the SVL. The foot, including the longest toe, is about 0.8 times the SVL. The hand has large oval palmar tubercles and two smaller thenar tubercles. Small and round subarticular tubercles are present on the fingers. The relative finger lengths are as follow: 4<1≤2<3. Manual webbing is absent. The tarsal tubercle is approximately the size of the outer metatarsal tubercle. The inner metatarsal tubercle is oval and larger that the rounded outer one. Pedal webbing is present among the basal phalanges (Barbour and Loveridge, 1927 reported no trace of webbing), and toe and fingertips are slightly expanded. The thumb of reproductive males has a large nuptial pad on dorsal and external side. Ovoid femoral glands, about half of femur length, are present in males. The dorsal skin is smooth without any dorsal ridges or warts. Eyelids are smooth, and no eyelid cornicle is present. The ventral skin is smooth. Vocal sac of males is about 0.75 times head width, extending over almost the entire length of the throat and anterior breast area, and bordered by two almost parallel folds of skin. The skin of the vocal sac is slightly granular.
The dorsum is a uniform dark brown or slate, almost black. Flanks have a well delimitated black stripe, starting behind the eye and stretching towards the hind legs and separated by a white line from a black spot in the groin area. This white line may extend anteriorly as of dorsolateral line. The dorsal surface of the forelegs is almost uniform dark brown; one dark blotch on the external surface of the upper and lower arms is present. The outer, posterior surface of thighs has a longitudinal and well defined white line over the second third of the thighs, stretching from the vent to the back of the knee (line sometimes shorter, not reaching knee). This line is bordered by uniform black. The anterior surface of the thighs are light brown with two to three black transverse bars. The lower leg dorsally is light brown with two black transverse bars. The loreal region is dark brown. The upper mandible is the same colour as the back, interrupted by three clearer blotches, one of them below eye. The lower mandible is dark brown with irregular small clearer spots. The vocal sac is almost uniform black. The belly has very large irregularly shaped dark brown blotches, separated by fine white lines, and the ventral side of thighs, lower leg and foot white have large dark brown blotches.
Phrynobatrachus maculiventris is a small to medium sized species (SVL < 26 mm) . Snout-vent length varies from 17.5-18.5 mm in males, and 20.6-25.2 mm in females (Rödel et al., 2004).
Frogs recorded by Guibé and Lamotte (1958) in the vicinity of the type locality near Doromou include Chiromantis rufescens, Phlyctimantis boulengeri, Hyperolius zonatus, Phrynobatrachus plicatus, P. fraterculus, Cardioglossa occidentalis, and Silurana tropicalis. Frog species recorded at the Diécké pond and its surroundings include Ptychadena bibroni, Phrynobatrachus fraterculus, and P. gutturosus. Frogs recorded in the surrounding forests: Hyperolius chlorosteus, Ptychadena aequiplicata, Phynobatrachus tokba, P. liberiensis, Cardioglossa occidentalis, and Arthroleptis sp. (Rödel et al., 2004; Rödel et al., 2009).
Phrynobatrachus maculiventris is known from Liberia, Guinea, and Côte d'Ivoire. In Liberia, the only record is a single individual collected at Peahtah, St. Paul's River (Barbour and Loveridge, 1927). In Guinea and Côte d'Ivoire, P. maculiventris has been recorded from a forest pond near Doromou at the foothills of Monts Nimba (Guibé and Lamotte, 1958), a few other sites around Monts Nimba (Ziéla, Yalé forest, Zouguépo forest, Zougué, Blà forest; Guibé and Lamotte, 1963), and a pond at the edge of Diécké Forest Reserve (Rödel et al., 2009).
The two localities with known habitat descriptions were in secondary and primary rainforests (Rödel et al., 2009).
Phrynobatrachus maculiventris seems to breed in larger, possibly permanent, stagnant waters towards the end of the rainy season (Guibé and Lamotte, 1958; Rödel et al., 2009). In Diécké, Guinea, adults were only captured at night in the surroundings of the pond in September-October. The comparatively large tadpoles were collected at the end of November and early December, while visits to the Diécké pond earlier in the rainy season revealed neither adults nor tadpoles. It is therefore believed that adults only occasionally live close to their breeding ponds. The tadpoles were collected from shallow water, laying completely exposed on leaf litter under overhanging shrubs. They were easily visible from outside the water and they were not hiding even when water disturbances occurred.