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West African torrent-frogs of the genus Odontobatrachus currently belong to a single species: Odontobatrachus natator (Boulenger, 1905). Recently, molecular results and biogeographic separation led to the recognition of five Operational Taxonomic Units (OTUs) thus identifying a species-complex. Based on these insights, morphological analy ses on more than 150 adult specimens, covering the entire distribution of the family and all OTUs, were carried out. Despite strong morphological congruence, combinations of morphological characters made the differentiation of OTUs successful and allowed

Astylosternus laticephalus sp. nov. Rödel, Hillers, Leaché, Kouamé, Ofori-Boateng, Diaz & Sandberger is described fromeastern Ivory Coast and western and central Ghana, and compared to Astylosternus occidentalis Parker, 1931 from thewestern part of the Upper Guinea forest zone (western Ivory Coast, Liberia, Guinea and Sierra Leone). Based on a com-prehensive sample, including specimens from the entire range, the latter species is re-described. The new species is char-acterized by a body shape typical for frogs of the genus Astylosternus, but has an exceptionally broad head, i.e. broaderthan in A. occidentalis. The basic dorsal pattern of A. laticephalus sp. nov. consists of a brownish to brownish red colour-ation with distinct red dots (red dots are only rarely present in A. occidentalis). The new species has bicoloured eyes withthe lower part of the iris being grey, the upper third of the iris is orange to red (A. occidentalis always has a uniform greyishiris). Males of the new species lack spines on the throat, belly (always present in A. occidentalis males), and a layer ofblack nuptial skin in the pectoral region (present in male A. occidentalis from western Guinea). Astylosternus laticephalussp. nov. differs from A. occidentalis by a mean pairwise genetic distance of 3.2% in the investigated part of the mitochon-drial 16S rRNA gene. Genetic divergence to the morphologically most similar Central African species, A. diadematus,was 11.9%. We briefly discuss the phylogenetic position of West African Astylosternus, hint on the possibility that thegenus might be paraphyletic and discuss the biogeography of West African Astylosternus, in particular with respect to forest cover fluctuations in the past.

Although Conraua goliath is well known as the largest living frog species, the diversity and evolution of the genus Conraua across sub-Saharan Africa remain poorly understood. We present multilocus phylogenetic analyses of the six currently recognized species that provide insights into divergence times, biogeography, body size evolution and undescribed species. An analysis of divergence times demonstrates that crown-group Conraua arose some time during the latest Oligocene to mid-Miocene followed by divergence into major lineages in the mid-Miocene that may reflect the fragmentation of widespread tropical forests in Africa that began at this time. We find three pairs of sister species, C. crassipes + C. beccarii, C. alleni + C. derooi and C. goliath + C. robusta, each of which diverged during the Miocene. These relationships reject phylogenetic hypotheses based solely on biogeography as the geographically peripheral C. beccarii from northeastern Africa is nested within western African species and the Central African species do not form a clade. Our species delimitation analyses provide support for undescribed species in C. alleni, C. beccarii and C. derooi, and possibly C. crassipes, suggesting that the current taxonomy substantially underestimates species diversity. There is no clear directional trend of either increasing or decreasing body size in Conraua and the three largest species do not form a clade. With a robust phylogenetic hypothesis in hand, further field-based studies are needed to understand the evolution of morphology and life history in this charismatic African anuran clade.

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