A needle in a haystack: Rediscovery and revised description of Ichnotropis microlepidota Marx, 1956, from the central highlands of Angola

Ichnotropis is a genus of small and elusive ground-dwelling lizards mostly distributed in the savannas and woodlands south of the Congo River. The genus comprises six nominal species and three subspecies; however, the phylogenetic hypothesis of this group and the taxonomical status of several taxa remain unresolved. Among these species, Ichnotropis microlepidota stands out, as it is only known from the type series since its discovery in the 1950 s in the crop of a Chanting Goshawk in Mount Moco, in the central highlands of Angola.

Consequently, due to the lack of a precise locality and its similar morphology to other species, the taxonomic status of this species has been debated by several authors. Thanks to the collection of new material across the Angolan territory, we take the opportunity to revise the group, using molecular and morphological techniques. Thus, we here provide the first phylogenetic hypothesis of the group in Angola and therefore a phylogenetic placement of I. microlepidota.

As a result, we validate the taxonomic status of this elusive species and demonstrate that it represents a distinct taxon within the bivittata group, differing by 14.99 % 16 S uncorrected p-distance from I. bivittata. Furthermore, we undertake an updated description of this species, providing additional external and internal (i. e., cranial osteology) morphological features that can be used to compare I. microlepidota with other members of the group.

Finally, we identified two candidate new species from Angola and corroborated the importance of the central highlands of Angola as an important center of endemism in the western slope of Central Africa.