Classification / Names
Common names | Synonyms | Catalog of Fishes (gen., sp.) | ITIS | CoL | WoRMS | Cloffa
Actinopterygii (ray-finned fishes) > Perciformes
(Perch-likes) > Cichlidae
(Cichlids) > Pseudocrenilabrinae
Etymology: Haplochromis: Greek, Haploos = single + Greek, chromis = a fish, perhaps a perch (Ref. 45335); vanoijeni: This species is named in honour of Dr. Martien J.P. van Oijen, ichthyologist of the Netherlands Centre of Biodiversity, Naturalis, in appreciation for his work on taxonomy and ecology of the haplochromine cichlids of Lake Victoria; Dr. van oijen was one of the pioneers of the Haplochromis Ecology Survey Team (HEST) of Leiden University that started its fieldwork on Lake Victoria in 1977 (Ref. 85523).
Environment: milieu / climate zone / depth range / distribution range
Freshwater; demersal. Tropical
Africa: Lake Victoria (Ref. 85523).
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 8.9 cm SL male/unsexed; (Ref. 85523)
Morphology | Morphometrics
Diagnosis: Haplochromis vanoijeni is a small sized (less than 9 cm standard length), micrognathic species with generalized body profile, but with a relatively long and acute snout; because of the latter, and its relatively small interorbital width, the species bears some resemblance with species of the 'tridens' group; indeed, it has some tricuspid teeth rostrally in the outer row of the oral jaws (Ref. 85523). It differs from eight of the nine described species in the 'tridens' group in the colouration of sexually active males: dorsum and flanks in sexually active males of Haplochromis vanoijeni are bright red; both males and females have conspicuously silverish-white cheeks, contrasting with the remaining head colours, which is a unique character among Lake Victoria haplochromines (Ref. 85523). From Haplochromis tridens, of which the colouration of live, sexually active males is unknown, it differs in the following characters: the lower jaw is shorter, lower jaw length 40.9-44.7% of head length vs. 43.3-51.8%; a larger interorbital width, 17.6-20.5% of head length vs. 15.0-19.5%; in contrast to H. vanoijeni, H. tridens has a dorsal head profile that is interrupted by a prominent premaxillary pedicel, and a cephalic line system with prominent pores (Ref. 85523). Besides by its specific colouration pattern, H. vanoijeni can be distinguished from all described species in the 'tridens' group by its larger body depth, 33.1-36.2% of standard length vs. 30.6-33.6%; the lower jaw of H. vanoijeni is shorter, 40.9-44.7% of standard length, than tah of most described species in the 'trident' group, except for that of H. cryptogramma and that of H. plutonius (Ref. 85523).
A benthic species, caught mainly in the deeper parts, more than 10 m depth, in the Mwanza Gulf, over mud bottoms; occasionally caught over mud in shallower areas (Ref. 85523). Before the ecological changes in Lake Victoria, this species fed mainly on detritus; occasionally remains of shrimps and insects were found (Ref. 85523). This species is a female mouth brooder (Ref. 85523).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
This species is a female mouth brooder (Ref. 85523).
de Zeeuw, M.P., M. Mietes, P. Niemantsverdriet, S. ter Huurne and F. Witte, 2010. Seven new species of detritivorous and phytoplanktivorous haplochromines from Lake Victoria. Zool. Meded. Leiden 84:201-250. (Ref. 85523)
IUCN Red List Status (Ref. 120744)
CITES (Ref. 115941)
Threat to humans
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningSpawning aggregationFecundityEggsEgg development
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingMass conversion
Estimates of some properties based on models
Phylogenetic diversity index (Ref. 82805
= 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.01445 (0.00677 - 0.03085), b=2.98 (2.81 - 3.15), in cm Total Length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245
Trophic Level (Ref. 69278
): 3.3 ±0.4 se; Based on size and trophs of closest relatives
Resilience (Ref. 69278
): High, minimum population doubling time less than 15 months ().
Vulnerability (Ref. 59153
): Low vulnerability (12 of 100) .