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Type: Article
Published: 2021-06-29
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A new critically endangered slippery frog (Amphibia, Conrauidae, Conraua) from the Atewa Range, central Ghana

Museum für Naturkunde Berlin – Leibniz Institute for Evolution and Biodiversity Science, Invalidenstraße 43, 10115 Berlin, German
CSIR-Forestry Research Institute of Ghana, P. O. Box 63, Fumesua, Kumasi, Ghana. EDGE of Existence Programme, Zoological Society of London, Regent’s Park, London NW1 4RY, UK.
Université Jean Lorougnon Guédé, UFR Environnement, Laboratoire de Biodiversité et Ecologie Tropicale, Daloa, BP 150, Côte d´Ivoire
Department of Natural History, Florida Museum of Natural History, University of Florida, Gainesville, Florida 32611, USA
Laboratory of Ecology and Ecotoxicology, Faculty of Sciences, University of Lomé, BP 6057 Lomé, Togo
Wild Chimpanzee Foundation (WCF), Liberia Office, FDA Compound, Whein Town, Mount Barclay, Montserrado County, Liberia
Museum für Naturkunde Berlin – Leibniz Institute for Evolution and Biodiversity Science, Invalidenstraße 43, 10115 Berlin, German
Department of Biology & Burke Museum of Natural History and Culture, University of Washington, Seattle, WA, USA
Museum für Naturkunde Berlin – Leibniz Institute for Evolution and Biodiversity Science, Invalidenstraße 43, 10115 Berlin, German
Amphibia Anura biodiversity hotspot conservation integrative taxonomy Upper Guinean Forest West Africa


Forty-nine years after the last description of a slippery frog, we describe a seventh species of the genus Conraua. The new Conraua is endemic to the Atewa Range Forest Reserve, central Ghana, and is described based on genetic, bioacoustics, and morphological evidence. Recent molecular phylogenetic and species delimitation analyses support this population as distinct from nominotypical C. derooi in eastern Ghana and adjacent Togo. The new species is sister to C. derooi, from which it differs ~4% in the DNA sequence for mitochondrial ribosomal 16S. Genetic divergences in 16S to other species of Conraua range from 4–12%. The new species is distinguished morphologically from its congeners, including C. derooi, by the combination of the following characters: medium body size, robust limbs, lateral dermal fringing along edges of fingers, cream ventral color with brown mottling, the presence of a lateral line system, indistinct tympanum, the presence of inner, outer, and middle palmar tubercles, and two subarticular tubercles on fingers III and IV. We compare the advertisement calls of the new species with the calls from C. derooi and find that they differ by duration, frequency modulation, and dominant frequency. We discuss two potential drivers of speciation between C. derooi and the new species, including river barriers and fragmentation of previously more widespread forests in West Africa. Finally, we highlight the importance of the Atewa Range Forest Reserve as a critical conservation area within the Upper Guinean biodiversity hotspot.



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