Abstract
Lamprologine cichlids include nearly 100 species from Lake Tanganyika, but only nine are known from the Congo River, including Lamprologus lethops, the only known blind cichlid. Little is known about its natural history. We characterized the complete mitochondrial genomes of L. lethops and seven related riverine species to infer evolutionary relationships. Genomes were similar in size and structure. Riverine Lamprologus formed two non-sister mitochondrial lineages more closely related to Lake Tanganyika lamprologines than to each other, suggesting past introgression or incomplete lineage sorting. Lamprologus lethops was sister to lower Congo River species. Broader taxonomic and genomic sampling is needed.