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Pseudotropheus johannii Eccles, 1973

Bluegray mbuna
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Image of Pseudotropheus johannii (Bluegray mbuna)
Pseudotropheus johannii
Male picture by Hagblom, F.

Classification / Names Common names | Synonyms | Catalog of Fishes(genus, species) | ITIS | CoL | WoRMS | Cloffa

Teleostei (teleosts) > Cichliformes (Cichlids, convict blennies) > Cichlidae (Cichlids) > Pseudocrenilabrinae
Etymology: Pseudotropheus: Greek, pseudes = false + Greek, tropaion = defeat, a memorial of a fighting war, trophy; because of their specialized teeth were such an obvious feeding adaptation (Ref. 45335).
Eponymy: John Johns was a collector of Lake Malawi fishes for the aquarium trade. ‘Johann’ is a German variant of John. Unfortunately, we have no further information about him. (Ref. 128868), visit book page.

Environment: milieu / climate zone / depth range / distribution range Ecology

Freshwater; benthopelagic; pH range: 8.0 - 8.0; dH range: 9 - 19. Tropical; 22°C - 25°C (Ref. 1672); 13°S - 14°S

Distribution Countries | FAO areas | Ecosystems | Occurrences | Point map | Introductions | Faunafri

Africa: endemic to Lake Malawi. Occurs in Masinje Rocks, Cape Ngombo.

Size / Weight / Age

Maturity: Lm ?  range ? - ? cm
Max length : 10.0 cm TL male/unsexed; (Ref. 5663)

Short description Identification keys | Morphology | Morphometrics

Males are brilliant sky blue to dark blue; the colors show a "checkerboard" pattern with alternating light and dark patches; several light-colored "egg spots" on their anal fin; females and juveniles bright yellow-orange in color (Ref. 44091).

Biology     Glossary (e.g. epibenthic)

Found in rocky habitats of shoreline areas (Ref. 58302). Omnivorous and feed on both plant and animal matter (Ref. 44091).

Life cycle and mating behavior Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae

Maternal mouthbrooders; males establish territories and maintain a harem of females; female deposits eggs and picks them up in the mouth for incubation; male spreads out his anal fin showing the "eggs pots"; the females mistake these spots for her eggs and try to also take them inside her mouth; the male then releases his milt and the female takes them in, thus fertilizing the eggs inside her mouth (Ref. 44091).

Main reference Upload your references | References | Coordinator : Kullander, Sven O. | Collaborators

Maréchal, C., 1991. Melanochromis. p. 258-265. In J. Daget, J.-P. Gosse, G.G. Teugels and D.F.E. Thys van den Audenaerde (eds.) Check-list of the freshwater fishes of Africa (CLOFFA). ISNB, Brussels; MRAC, Tervuren; and ORSTOM, Paris. Vol. 4. (Ref. 5663)

IUCN Red List Status (Ref. 130435: Version 2024-2)

  Least Concern (LC) ; Date assessed: 20 June 2018

CITES

Not Evaluated

CMS (Ref. 116361)

Not Evaluated

Threat to humans

  Harmless





Human uses

Aquarium: commercial
FAO - Publication: search | FishSource |

More information

Trophic ecology
Food items
Diet composition
Food consumption
Food rations
Predators
Ecology
Ecology
Population dynamics
Growth parameters
Max. ages / sizes
Length-weight rel.
Length-length rel.
Length-frequencies
Mass conversion
Recruitment
Abundance
Life cycle
Reproduction
Maturity
Maturity/Gills rel.
Fecundity
Spawning
Spawning aggregations
Eggs
Egg development
Larvae
Larval dynamics
Anatomy
Gill area
Brain
Otolith
Physiology
Body composition
Nutrients
Oxygen consumption
Swimming type
Swimming speed
Visual pigments
Fish sound
Diseases & Parasites
Toxicity (LC50s)
Genetics
Genetics
Heterozygosity
Heritability
Human related
Aquaculture systems
Aquaculture profiles
Strains
Ciguatera cases
Stamps, coins, misc.
Outreach
Collaborators
References
References

Tools

Special reports

Download XML

Internet sources

AFORO (otoliths) | Alien/Invasive Species database | Aquatic Commons | BHL | Cloffa | BOLDSystems | Websites from users | Check FishWatcher | CISTI | Catalog of Fishes: genus, species | DiscoverLife | ECOTOX | FAO - Publication: search | Faunafri | Fishipedia | Fishtrace | GenBank: genome, nucleotide | GloBI | Google Books | Google Scholar | Google | IGFA World Record | MitoFish | Otolith Atlas of Taiwan Fishes | Public aquariums | PubMed | Reef Life Survey | Socotra Atlas | Tree of Life | Wikipedia: Go, Search | World Records Freshwater Fishing | Zoobank | Zoological Record

Estimates based on models

Phylogenetic diversity index (Ref. 82804):  PD50 = 0.5000   [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.01445 (0.00674 - 0.03099), b=2.99 (2.82 - 3.16), in cm total length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245).
Trophic level (Ref. 69278):  2.0   ±0.0 se; based on diet studies.
Resilience (Ref. 120179):  Medium, minimum population doubling time 1.4 - 4.4 years (Fec<1000).
Fishing Vulnerability (Ref. 59153):  Low vulnerability (10 of 100).