Palaeoplex palimpsest Schedel, Kupriyanov, Katongo & Schliewen, 2020
20-sty-2020 — Two new genera and species of riverine cichlids from Zambia have been described
By Juan Miguel Artigas Azas
Two new species of Pseudocrenilabrini riverine cichlids from Zambia have been described by Frederic D.B. Schedel, V.M.S. Kupriyanov, C. Katongo, and Uldrich Schliewen in the journal Zootaxa. Each one of this species has been given a new monotypic genus. Both relatively recently discovered species species had been found in nuclear and mitochondrial DNA comparisons to belong to ancient evolutive lineages older than any Pseudocrenilabrus species, which has inspired their description in monotypic genera. Their diagnosis relies mainly on subtle differences of their osteology, where the distance between the first two of a series of five small bones under the eye is used. Lufubuchromis relictus is native (as its generic name implies) to the Lufubu River (both above and below the Lufubu hydroelectric dam), which discharges into Lake Tanganyika. The specific name relictus (residue from Latin), refers to the restricted distribution of this species in the isolated upper region of an ancient plateau, where its phylogenetic position as the ancient mitochondrial sister group of all other members of the Pseudocrenilabrus lineage suggests that it represents a relict ancient evolutionary lineage. Palaeoplex palimpsest is known from the Luongo River, a tributary of Luapula River, and from several locations in the Kalungwishi River drainage, both rivers drain into Lake Mweru, and are part of the Congo River drainage. The etymology of this species is as elaborated as the diagnosis; A palaeoplex is a concept in geoecodynamics, the study of changes in geology and ecology in a given area (landscape) over time. A palaeoplex describes the full genetic variation of a given species in a given landscape over a given time, as this genus is believed to have evolved in a particular ancient landscape. A palimpsest is a parchment manuscript page, most commonly used in medieval times, that has been secondarily overwritten after layers of old handwritten letters had been scraped off, sometimes repeatedly.
Schedel, Frederic D. B & V.M.S. Kupriyanov, C. Katongo, U.K. Schliewen. 2020. "Palaeoplex gen. nov. and Lufubuchromis gen. non, two new monotypic cichlid genera (Teleostei: Cichlidae) from northern Zambia". Zootaxa. 4718(2):191–229. DOI: 10.11646/zootaxa.4718.2.3 (crc02709) (streszczenie)