Comprehensive DescriptionRead full entry
Diagnosis and Description: Blommersia angolafa is a small frog, with a body size of 17-21 mm, enlarged tips on fingers and toes (less developed in other species of Blommersia), and lacks any dark area in the tympanic and frenal region, (present in other species of Blommersia). The following set of characteristic features also assign this species to the genus Blommersia: patch-like femoral glands of type 2 in males, presence of weakly expressed webbing between toes, presence of small-sized inner and outer metatarsal tubercles and a single and moderately distensible subgular vocal sac.Similar species: see B. grandisonae. Although both B. angolafa and B. grandisonae have enlarged finger tips, they are much more developed in B. angolafa.
Coloration and Variation: B. angolafa has a rather uniform dorso-lateral colouration, shading from yellowish-light brownish to dark brown, with light-bluish spots on the flanks and light-bluish terminal parts of the fingers and toes. The species also appears to be chromatically sexually dimorphic. Males differ from females in having a light colouration, while females are more brownish. After 2 years in preservative, the back has faded to light-yellowish shading to whitish, with a rather indistinct pattern of white spots on the flanks. The white-coloured tips of fingers and toes are no longer evident.
Phylogenetic Relationships: The authors consider the reproductive mode of B. angolafa as a derived character, having evolved from the more typical reproduction in lentic water bodies. The general scarcity of lentic habitats in Malagasy rainforests may have provided the conditions that favoured the evolution of this phytotelmic breeding strategy.
Etymology: One of the authors (C. J. Raxworthy) first used this name when he found the new Blommersia at Masoala. The term "angolafa" or "angolafo" is the Malagasy vernacular name used at that region by the Betsimisaraka people for the Dypsis palm species (mostly for Dypsis lastelliana), whose leaves and prophylls are used by the new Blommersia species.