New insights into the taxonomic status, distribution and natural history of De Witte’s Clicking Frog (Kassinula wittei Laurent, 1940)

Abstract

Kassinula is a monotypic genus of small frog in the family Hyperoliidae, only represented by Kassinula wittei. This species morphologically resembles both Kassina Girard, 1853 and Afrixalus Laurent, 1944, and its taxonomic status has been debated for decades. It has previously been subsumed within Kassina, and is currently placed as a sister genus to Afrixalus, although it has not been included in any phylogenetic studies until now. This species is poorly represented in museum collections and is only known from fewer than 35 specimens from southern Democratic Republic of the Congo and adjacent Zambia. Newly collected material from central Angola, a range extension of 400–800 km west of previously known localities, allowed us to revisit the taxonomic placement of the genus with the aid of phylogenetic analysis and shed light on its geographic distribution, morphology and natural history. Although our phylogenetic analysis is limited to a single mitochondrial gene (16S), we place Kassinula in the subfamily Hyperoliinae and closely related to Afrixalus, with a high degree of confidence. Further phylogenetic studies are needed before formally synonymising Afrixalus with Kassinula.