A NEW SQUEAKER FROG (ARTHROLEPTIDAE: ARTHROLEPTIS) FROM THE MOUNTAINS OF CAMEROON AND NIGERIA

A new species of squeaker frog (genus Arthroleptis) is described from the northern mountains of the Cameroon Volcanic Line, a species-rich region within the West African biodiversity hotspot This new species is associated with human-altered landscapes, including farms and grasslands, and is known from the highland areas near Bamenda. including Mt Oku, Cameroon, as well as the Obudu and Mambilla Plateaus of eastern Nigeria The known distribution suggests that it may eventually also be found throughout the Acha-Tugi Ridge that traverses the Cameroon-Nigeria border More than 40,ears ago, a specimen from one of these populations was recognized as probably representing a new species, but no further work was published on this material We posit that the taxonomy of tins new species has proven problematic because of morphological similarity to Arthroleptis poecilonotus Although in some ways resembling A poecilonotus, a molecular phylogeny based on mitochondrial gene sequence data demonstrates that the new species is not closely related to A poecilonotous and, instead, forms a clade with A krokosua, A perrcti and A variabilis The new species is diagnosable by the combination of medium-small body size (24-29 mm snont-vent length in adult females), the color patterns of the venter and head, and a relatively stout hindlimb with a prominentinnei metatarsal tubercle The description of this new species further highlights these mountains as an Important regain of endemism within the Cameroon Volcanic Line