First record of foulassi screeching frog, arthroleptis adelphus (Perret, 1966) (Anura, Arthroleptidae, arthroleptinae), from Nigeria, with notes on its phylogenetic position

We report the first known occurrence of the Foulassi Screeching Frog, Arthroleptis adelphus (Perret, 1966), from Nigeria. A specimen of A. adelphus was collected during herpetological survey work conducted in Cross River National Park, south-eastern Nigeria. Morphometrics and mitochondrial 16S rRNA gene confirm identity of the specimen. Matrilineal genealogy reveals a sister relationship of A. adelphus from Nigeria with individuals from south-western Cameroon. Genetic analysis further shows geographic structuring and divergence among populations of A. adelphus from the Guineo–Congolian forest region. We offer updates to the IUCN geographic range of A. adelphus.