No abstract

The girdled lizard genus Cordylus is represented in Angola by two species, Cordylus angolensis and C. machadoi, separated from their nearest congeners by over 700 km. Here we describe a new species, Cordylus namakuiyus sp. nov., endemic to the arid lowlands west of the southern Angolan escarpment. Phylogenetic analysis using three mitochondrial and eight nuclear genes shows that the low-elevation forms and the proximate, high-elevation species C. machadoi are genetically divergent and reciprocally monophyletic, and together form the earliest diverging lineage of the northern Cordylus clade. Morphological data, collected using computed tomography and traditional techniques (scalation and morphology), identify consistent phenotypic differences between these high-and low-elevation species and allows for a detailed description of the osteology and osteodermal arrangements of the new species. A series of 50 specimens, collected during the 1925 Vernay expedition to southwestern Angola and housed at the American Museum of Natural History, are assigned to the new species, although the identity of Cordylus from northern Namibia remains ambiguous and requires further investigation.Key words: computed tomography, girdled lizard, Kaokoveld, molecular phylogeny, ontogeny, osteoderms, osteology ResumoOs largatos espinhosos das género Cordylus estāo representados em Angola por duas espécies, Cordylus angolensis e C. machadoi, separados dos seus congéneres mais próximos por uma uma distância superior a 700 km. Neste artigo, descreve-se uma nova espécie, Cordylus namakuiyus sp. nov., endémica do planícies áridas a oeste da escarpa sul de Angola. Análises filogenéticas com base em três genes mitocondriais e oito genes nucleares demonstram que as formas da zona de baixa elevaçāo e a espécie vizinha que ocorre nas áreas mais elevadas, C. machadoi, sāo geneticamente divergentes e reciprocamente monofiléticas, e que juntas constítuem a linhagem divergente mais antiga do clado norte do género Cordylus. Dados morfológicos, recolhidos através de tomografia computacional e técnicas mais tradicionais (contagem de escamas e morfometria), identificam diferenças fenotípicas consistentes entre as espécies de baixa e alta elevaçāo e permitem uma descriçāo detalhada da osteologia e distribuiçāo dos osteodermos da nova espécie. Uma série de 50 espécimes, colectados na expediçāo de Vernay ao sudoeste de Angola em 1925, e actualmente depositados no American Museum of Natural History, sāo atribuídos à nova espécie, embora a identificaçāo de um Cordylus do norte da Namibia permaneça ambígua e necessite de investigaçāo mais detalhada. STANLEY ET AL.202 · Zootaxa 4061 (3)

African pygmy toads of the genus Poyntonophrynus are some of the least known species of African toads. The genus comprises ten recognized species endemic to sub-Saharan Africa, five of which are restricted to southwestern Africa. Recent field research in Angola provided new material for three species of Poyntonophrynus, including a morphologically distinctive population from the Serra da Neve Inselberg. Based on a combination of external morphology, high-resolution computed tomography scanning, and molecular phylogenetic analysis, the Serra da Neve population is described as new species that is nested within the genus. The most striking character that differentiates the newly described species from its congeners is the lack of a tympanic middle ear, a condition common in the family Bufonidae, but so far not known for Poyntonophrynus. The description of this new species from southwestern Angola reinforces the biogeographic importance of the region and further suggests that southwestern Africa is the cradle of diversity for this genus.

Angola and the Democratic Republic of the Congo are relatively unknown in terms of their herpetological diversity. Based on specimens collected in the Congolese region of the Katanga and the northeast of Angola during the first decades of the twentieth century, de Witte and Laurent independently suggested, based on morphological and coloration differences, that populations of T. megalura of these regions could belong a new “race”. We compared specimens of T. megalura (including the type specimens of T. megalura and T. massaiana) with Angolan and Katangan museum specimens as well as newly collected specimens from Angola. Coloration pattern and morphological characters, in combination with substantial divergence in the 16S mitochondrial gene, confirm the distinctiveness of the west Central African form, and it is here described as a new species. Data regarding its natural history, ecology and global distribution are presented.