Refine
Document Type
- Part of Periodical (5)
- Article (1)
Language
- English (6)
Has Fulltext
- yes (6)
Is part of the Bibliography
- no (6)
Keywords
- integrative taxonomy (2)
- Adaptive radiation (1)
- COI (1)
- Cichliformes (1)
- East Africa (1)
- Enteromius cercops (1)
- Enteromius perince (1)
- Enteromius stigmatopygus (1)
- Harpagochromis (1)
- Lake Tanganyika basin. (1)
- Lake Victoria basin (1)
- Mozambique (1)
- Prognathochromis (1)
- haplochromine cichlid (1)
- haplochromines (1)
- mouth-brooding cichlids (1)
- new specie (1)
- pharyngeal jaw proportions (1)
- species richness (1)
- synonym (1)
- synonymy (1)
- trophic ecology (1)
- ‘Barbus’ (1)
A new paedophagous species of Protomelas, P. krampus sp. nov., is described from Lake Malawi. It has been found in Lukoma Bay in Tanzania, near Mara Point in Mozambique, and at Otter Point, Chizumulu, the Likoma Islands and Mazinzi Reef in Malawi. This species is placed in the genus Protomelas based on its melanin pattern, which comprises a continuous midlateral stripe. A morphometric study was done to compare this species with its congeners and similar species of Hemitaeniochromis and Caprichromis. It differs from most congeners by having only one inner tooth row. Furthermore, P. krampus sp. nov. differs from P. insignis, P. spilopterus, H. brachyrhynchus, H. urotaenia, Caprichromis liemi and C. orthognathus by its shorter premaxillary pedicel, shorter prepectoral distances and dentition. It also differs largely in its melanin pattern from the paedophagous species C. liemi, C. orthognathus, Diplotaxodon greenwoodi and Naevochromis chrysogaster, as well as H. brachyrhynchus and H. urotaenia. Protomelas krampus sp. nov. has been observed to ram mouth-brooding cichlids from above to feed on their eggs or larvae.
A taxonomic revision of the cichlid genus Astatoreochromis is presented. Eighteen meristic and 23 morphometric measurements were taken on 185 individuals, including type specimens. While fin counts separate populations from the Lake Victoria region (Astatoreochromis alluaudi) from those of the Rusizi and Malagarazi rivers in the Lake Tanganyika basin (A. vanderhorsti and A. straeleni respectively), clear differentiation was not detected between the latter two. Mann-Whitney U-tests on specimens of comparable size from the two Tanganyika populations revealed significant differences in specimens < 75 mm SL, mainly in pharyngeal jaw proportions, but also in some other measurements on the head and body. However, these differences were not detected in specimens > 75 mm SL and Astatoreochromis vanderhorsti is herein considered a junior synonym of A. straeleni. A redescription of the two valid species of Astatoreochromis, A. alluaudi and A.straeleni, is provided.
Piscivory is a common trophic niche among cichlids of the East African Great Lakes, including Lakes Edward and George. From these two lakes, we examined the taxonomic diversity of cichlid species with a piscivorous morphology. Prior to this study, two piscivorous species were formally described, Haplochromis squamipinnis and H. mentatus. We redescribe both species and describe an additional ten new species of Haplochromis with a piscivorous morphology: H. latifrons sp. nov., H. rex sp. nov., H. simba sp. nov., H. glaucus sp. nov., H. aquila sp. nov., H. kimondo sp. nov., H. falcatus sp. nov., H. curvidens sp. nov., H. pardus sp. nov., and H. quasimodo sp. nov. All twelve species differ in dominant male colour pattern (unknown for H. latifrons sp. nov. and H. curvidens sp. nov.) and morphological traits. The species can be divided into two morphological groups: the macrodontic piscivores and the microdontic piscivores. This division potentially reflects an ecological differentiation in habitat use, hunting technique, prey species, and prey size. We conclude that some 12–20% of the species from the cichlid assemblage of Lake Edward have a piscivorous morphology.
A revision was done on the species of Enteromius Cope, 1867 (Cypriniformes: Cyprinidae) from the Lake Edward system with a smooth, flexible third unbranched dorsal fin ray without serrations. Specimens with these characteristics had previously been attributed to E. perince and E. stigmatopygus. A combination of a genetic (COI, mtDNA) and a morphometric approach was used. Based on the COI gene, we found two groups with a distance of 8.5%, though neither of the two corresponded to E. perince or E. stigmatopygus. One group revealed to be conspecific with E. alberti, previously a synonym of E. stigmatopygus, described from the Rutshuru River, May-Ya-Moto (DRC, Lake Edward system), and revalidated here. In addition, E. cercops, described from the Nzoia River (Kenya, Lake Victoria basin), is put in synonymy with E. alberti. The second group was most similar to E. mimus, but differed morphologically somewhat from the types of E. mimus. Therefore, specimens of this group were identified as E. cf. mimus. Morphologically, E. alberti can be separated from E. cf. mimus based on a higher number of lateral line scales and smaller values for interorbital width, pre-pelvic distance, body depth, maximum and minimum caudal peduncle depth, head width and head depth.
One of the main challenges to adequately conserve the African fish fauna is to improve our so far unsatisfactory taxonomic knowledge of important portions of the ichthyofauna. In the present study, we attempted to unravel the taxonomic diversity of some species of Enteromius Cope, 1867, a problematic African fish genus, recently collected in the north-eastern part of the Congo basin. We used an integrative approach, combining DNA barcodes and morphological analyses. For one of the species complexes found, the E. miolepis/eutaenia species complex, we evaluated taxonomic diversity over a larger geographic scale within the Congo drainage system. Although initial literature-based species identifications allowed us to assign all examined specimens to four tentative species, DNA barcodes indicated the presence of 23 distinct mitochondrial lineages. The majority of these lineages appeared endemic to particular rivers, and in most rivers multiple lineages occur in sympatry. Subsequent exploratory morphometric analyses indicated that almost all these lineages are morphologically distinguishable and that they may therefore represent undescribed species. As only a part of the Congo basin and a subset of the species diversity within Enteromius were examined, it appears that the species richness of Enteromius in the Congo basin is severely underestimated.