On the validity and distribution of Hemichromis angolensis (Cichliformes: Cichlidae)

Abstract Hemichromis angolensis , a species described for the Kwanza River in Angola, was recently revalidated based on molecular data which included only specimens from the Okavango. Further, a neotype was selected from a locality different from its type locality, the Calandula Falls, in the Lucala River, a tributary of the Kwanza River. The present study aims to investigate the distribution and species limits within the five-spot Hemichromis using DNA-barcoding and species delimitation methods. Cytochrome Oxidase subunit I (COI) gene partial sequences of eleven Hemichromis specimens distributed in the upper Zambezi, southern Congo, and Kwanza rivers were sequenced and incorporated to a 56 sequences dataset. Four different species delimitation methods assisted in defining OTUs for the dataset. Kwanza specimens were not grouped with specimens from the Okavango and upper Zambezi in any of the approaches, instead, all suggest that specimens from the Kwanza River and Lower Guinea belong to the same OTU or represent closely related OTUs. Based on information present on Hemichromis angolensis original description the neotype designation by Lamboj & Koblmüller (Lamboj and Koblmüller, Hydrobiologia 850:2177–2198, 2022) is rejected, and a new neotype is selected for H. angolensis which is herein assigned to the genus Serranochromis and represent a valid species Serranochromis angolensis .