AMPHIBIAWEB
Petropedetes palmipes
family: Petropedetidae

© 2005 Dave Blackburn (1 of 1)
Conservation Status (definitions)
IUCN (Red List) Status Endangered (EN)
CITES
Other International Status None
National Status None
Regional Status None

Country distribution from AmphibiaWeb's database: Cameroon, Equatorial Guinea, Gabon

 

View distribution map using BerkeleyMapper.

   

From the Encyclopedia of Life account:

Etymology

This species is named for the Latin 'palma" meaning hand and 'pes' meaning foot, referring to the webbed toes.


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

Summary

This species is associated with flowing waters within rocky areas of lowland forest and is restricted to Cameroon, mainland Equatorial Guinea, and Gabon. It is considered Endangered.


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

Distribution

This species is known only from the western slope of the southern Cameroon plateau, Cameroon, from Monte Alen in mainland Equatorial Guinea, and from Barrage de Kinguele in north-western Gabon (Amiet and Burger, 2004).


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

Morphology

The following is from the original description by Boulenger (1905):

Tongue is rather feebly notched behind, with a conical papilla in the middle. Vomerine teeth are in two short transverse or oblique series behind the level of the choanae. Head is strongly depressed, as long as broad. Snout is obtusely pointed, a little shorter than the orbit, with obtuse cathus rostralis and a very oblique, concave loreal region. The interorbital space is narrower than the upper eyelid. Tympanum is rather indistinct, about one third the diameter of the eye. Fingers are rather elongate, with large, cordiform terminal disks. The first finger is shorter than second. The toes are moderately elongate, webbed to the discs, which are a little smaller than those of the fingers. Subarticular and inner metatarsal tubercles are feebly prominent. The tibio-tarsal articulation reaches beyond the tip of the snout. The tibia is three-fifths to two-thirds as long as head and body. The foot is nearly half as long as head and body.

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Mean head width in males is about 41% of SUL, in females about 37%. Eye diameter is about 1.7 times eye-narial distance. Tympanum is very small and indistinct (tympanum / eye in males: 0.18–0.23, in females: 0.20–0.25). Tympanic papilla is absent. A supratympanic fold is present and distinct. Fingers are slender, with typically T-shaped fingertips. The relative length of fingers are as follows: III > IV > II > I. Manual subarticular tubercles are single. Manual webbing is absent. Palmar tubercle and thenar tubercles are present; palmar tubercle may be indistinct. Forearm hypertrophy is moderately developed in males. Carpal spike is present in males. Spinosities cover the entire body. Skin structure is heterogeneous with some larger warts on the flanks and back, otherwise skin texture on flanks and dorsum is similar. Ventral skin is more granular than in other species. Mean femur length in males is 53% of SUL, in females 51%. Mean tibia length in males is 58% of SUL, in females 57%. Mean foot length in males is 73% of SUL, in females 72%. Upper hind limbs of moderate size. Lower hind limbs are slender. Femoral glands larger in males than in females (femoral gland / femur length in males: 0.26–0.38, in females: 0.22–0.31) Relative length of toes is as follows: IV > III > V > II > I. Toes are fully webbed (Barej et al., 2010).

Skin is shagreened or glandular above with a more or less distinct glandular line along the middle of the head and body. The ventral parts are smooth. Males exhibit an internal vocal sacs and a well-defined large oval gland on the lower side of the thigh. Dorsum is dark olive, spotted or marbled with darker and lighter. Limbs have broad, dark and narrow, light cross-bars. Venter is whitish (Boulenger, 1905). According to Lamotte et al. (1959) adults are of a glossy black colour in life, and therefore hard to find between stones.


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

Size

Holotype measured 53 mm from snout to vent (Boulenger, 1905). According to Barej et al. (2010), females are slightly larger than males (SUL in males: 40.3–57.8 mm, in females: 37.5–54.7 mm).


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

Diagnostic Description

Medium to large-sized Petropedetes with a robust body shape. Tympanum is indistinct. Breeding males exhibit the following: tympanic papilla absent, moderate forearm hypertrophy, carpal spike present, spinosities covering the entire body, femoral glands of moderate size by prominent. Toes are fully webbed (Barej et al., 2010).


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

Comparisons

Snout more pointed than in other species. y the amount of webbing it can easily be differentiated from those with half-webbed toes, including P. cameronensis and P. juliawurstnerae, and the rudimentary-webbed species, including P. euskircheni, P. johnstoni, P. parkeri and P. vulpiae. P. perreti is the only other Central African Petropedetes that is fully webbed. P. palmipes can be easily distinguished from P. perreti by the size of the tympanum, which is very small and rather indistinct in both sexes of P. palmipes, while it is large and distinct in P. perreti. In addition, breeding males of P. perreti possess a tympanic papilla, which is lacking in P. palmipes (Barej et al., 2010).


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

Habitat and Ecology

It lives in rocky areas in lowland forest, usually near flowing water, and cannot survive significant modification of its forest habitat (Amiet and Burger, 2004).


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

Population Biology

This is a rare species (Amiet and Burger, 2004).


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

Activity and Special Behaviors

Barej et al. (2010) caught this species at night in primary forest among stones in a stream. The full webbing of adults suggests that this species is primarily aquatic (Barej et al., 2010).


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

Reproduction

The eggs are laid, and the larvae develop on rocks in the splash zones of streams and small waterfalls (Amiet and Burger, 2004).


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

Tadpole morphology

Lamotte et al. (1959) found tadpoles in high numbers in small rocky pools at the foot of rapids. The general coloration of the tadpoles is grey on dorsum and flanks, a duller colour around eyes and nostrils. The venter is translucent, and the intestinal tract is visible. The overall body shape is flat. Large eyes are situated in the first third of bod. The tail almost twice as long as body, and tail tip is pointed. Jaw sheats are small, narrow and serrated. The keratodont formula in younger stages is 4:3+3//1+1:5 and 3+3//1+1:2 in older ones. Schiøtz (1966) associates the change in keratodont with a changes in biology; younger larvae are rheophilous and older ones are semiterrestrial, scraping algae off stones. More developed tadpoles are darker than those at earlier stages. Tadpoles do not exceed a total length of 35 mm (25 mm being tail; Lamotte et al. 1959).


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

Phylogenetics

A genetic comparison of a fragment of the mitochondrial 16S rRNA gene (611 bp, including gaps) by Barej et al. (2010) found that interspecific comparison between P. palmipes and all other Central African Petropedetes taxa resulted in uncorrected p-distances that ranged between 7.80%-11.76% with this species most closely related to P. euskircheni.


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 Endangered because its Extent of Occurrence is less than 5,000 km2, all individuals are in fewer than five locations, and there is continuing decline in the extent and quality of its habitat in southern Cameroon, Equatorial Guinea, and northern Gabon (Amiet and Burger, 2004).


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

Trends

Populations of this species are decreasing (Amiet and Burger, 2004).


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

Threats

It is presumably threatened by the loss of forest habitat for agriculture, logging and human settlements (Amiet and Burger, 2004).


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

Conservation Actions and Management

It occurs in Monte Alen National Park in Equatorial Guinea and Monts de Cristal National Park in Gabon; it may occur in Campo Ma'an National Park in Cameroon (Amiet and Burger, 2004).


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