 |
| Haplochromis rex, H. aquila, Haplochromis simba, H. kimondo, Haplochromis glaucus, H. falcatus, Vranken, Van Steenberge, Heylen, Decru & Snoeks, 2022 |
ABSTRACT
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.
Keywords: Adaptive radiation, haplochromines, Harpagochromis, Prognathochromis, new species
Phylum Chordata Haeckel, 1874
Class Actinopterygii Klein, 1885
Order Cichliformes Betancur-R et al., 2013
Family Cichlidae Bonaparte, 1840
Subfamily Pseudocrenilabrinae Fowler, 1934
Tribe Haplochromini Poll, 1986
Genus Haplochromis Hilgendorf, 1888
Haplochromis Hilgendorf, 1888: 76
(as a subgenus of Chromis Cuvier, 1814).
Haplochromis mentatus Regan, 1925
Etymology: Specific name not explained in original description, probably derived from the Latin ‘mentum’ for ‘chin’; probably referring to the protruding lower jaw (i.e., projecting lower jaw sensu Regan 1925).
Haplochromis squamipinnis Regan, 1921
Etymology: Specific name not explained in original description, from the Latin ‘squamus’ for ‘scale’, and ‘pinnis’ for ‘fin’; probably referring to minute scales on basal parts of dorsal and anal fins.
Haplochromis latifrons sp. nov.
Etymology: Specific name from Latin ‘latus’ for ‘wide’ and ‘frons’ for ‘forehead’; referring to very broad interorbital area for a piscivorous species.
Haplochromis rex sp. nov.
Etymology: Specific name from the Latin ‘rex’ for ‘king’ (one that holds a preeminent position); referring to very small eyes, deep cheeks, and strong jaws set with large and acute teeth indicating this piscivore has most specialised morphology among all piscivores from the Lake Edward system to hunt on large prey (Barel et al. 1977).
Haplochromis simba sp. nov.
Etymology: Specific name from Swahili ‘simba’ for ‘lion’; referring to yellow body, orange cheeks that resemble manes, and predatory morphology.
Haplochromis glaucus sp. nov.
Etymology: Specific name from the Latin ‘glaucus’ for ‘greyish blue’; referring to grey and light-blue colour pattern of all adult specimens.
Haplochromis aquila sp. nov.
Etymology: Specific name from the Latin ‘aquila’ for ‘eagle’; referring to predatory morphology and large eyes.
Haplochromis kimondo sp. nov.
Etymology: Specific name from the Swahili ‘kimondo’ for ‘meteor’; referring to blunt head, pyriform body with mid-lateral band, and yellow colouration of ventral part of body.
Haplochromis falcatus sp. nov.
Etymology: Specific name from the Latin ‘falcatus’ for ‘sickle-shaped’; referring to acutely pointed sickle-like outer oral teeth.
 |
Haplochromis rex sp. nov. a. c–d. Photographs of freshly caught specimens. c. Holotype, a dominant male. d. A female (RMCA 2017.006.P.0355; 135.7 mm SL) to illustrate the live colour patterns. Haplochromis simba sp. nov. c–d. Photographs of freshly caught specimens. c. Dominant male (RMCA 2016.035.P.0224; 97.9 mm SL). d. Female (RMCA 2018.008.P.0348; 109.0 mm SL) to illustrate the live colour patterns. Haplochromis glaucus sp. nov. c–d. Photographs of freshly caught specimens. c. Dominant male, the holotype. d. Female (RMCA 2019.002.P.0017; 102.1 mm SL) to illustrate the live colour patterns. Haplochromis kimondo sp. nov. c–d. Photographs of freshly caught specimens. c. Holotype, a dominant male. d. Female (RMCA 2018.008.P.0364; 128.1 mm SL) to illustrate the live colour patterns. Haplochromis falcatus sp. nov. c–d. Photographs of freshly caught specimens. c. Dominant male (RMCA 2017.006.P.0416; 119.1 mm SL). d. Female (RMCA 2016.035.P.0257; 112.8 mm SL) to illustrate the live colour patterns. Haplochromis curvidens sp. nov. c–d. Photographs of freshly caught specimens. c. Holotype, an adult male. d. Female (RMCA 2018.008.P.0340); 90.2 mm SL) to illustrate the live colour patterns. Haplochromis quasimodo sp. nov. c–d. Photographs of freshly caught specimens. c. Dominant male (RMCA 2018.008.P(HP3072); 123.7 mm SL). d. Female (RMCA 2018.008.P(HP3064); 116.6 mm SL) to illustrate the live colour patterns. Haplochromis squamipinnis Regan, 1921. c–d. Photographs of freshly caught specimens. c. Dominant male (RMCA 2016.035.P.0250; 169.7 mm SL). d. Female (RMCA 2016.035.P(HP823); 129.6 mm SL) to illustrate the live colour patterns. The contrast was slightly enhanced. |
Haplochromis curvidens sp. nov.
Etymology: Specific name from the Latin ‘curvus’ for ‘curvature’, and ‘dentatus’ for ‘tooth’; referring to strongly recurved oral teeth.
Haplochromis pardus sp. nov.
EtymologySpecific name from the Latin ‘pardus’ for ‘leopard’; referring to nearly uniform black to yellow-pink flanks with clear black blotches, i.e., interrupted horizontal and vertical stripes.
Haplochromis quasimodo sp. nov.
Etymology: Specific name from Quasimodo, hunchbacked character in Victor Hugo’s novel ‘Notre-Dame de Paris’ (1831); referring to rather shallow head and deep and rhomboid bodies of large specimens.
Nathan Vranken, Maarten Van Steenberge, Annelies Heylen, Eva Decru and Jos Snoeks. 2022. From A Pair to A Dozen: The Piscivorous Species of Haplochromis (Cichlidae) from the Lake Edward System. European Journal of Taxonomy. 815(1), 1-94. DOI: 10.5852/ejt.2022.815.1749
