Aquarist Atlas
↑ Collection form of Petrotilapia nigra

Petrotilapia nigra "Thumbi West Island"

Thumbi West Island — TOOM-bee WEST EYE-land (approx.)

The fish

How this cichlid is built, and everything about how it lives, eats and breeds, is shared with the species — this page doesn't repeat it.

Read the full Petrotilapia nigra account →

Specific to Thumbi West Island

  • Collection locality & coordinates
  • Local coloration — best judged from the living-fish photo
  • Kept as a single-provenance line, never crossed with other collection points

Care facts below are the species' — shared with Petrotilapia nigra.

IUCNLEAST CONCERN · 2018
CARESNOT LISTED
Scientific size4.8 in12.2 cm standard length
Temperature75–82 °F24–28 °C
pH7.7–8.8alkaline
Depth0–115 ft0–35 m
DietCombs aufwuchs from rock
BreedingMaternal mouthbrooderGenus-typical small clutch of a few dozen eggs (not documented for this species)
Sexual dimorphismYesDominant males are blue-black with gray-brown bars, a dark blue cheek and black throat; females and non-territorial males are a plain beige to yellowish.
PhotographsSee photosGoogle Images →

The Thumbi West Island population

Petrotilapia nigra "Thumbi West Island" is the Thumbi West Island population of Petrotilapia nigra, a geographic colour form from the Malawi coast of Lake Malawi in the southern part of the lake. It is the same species as Petrotilapia nigra, distinguished by its collection locality and local coloration; aquarists keep and breed it as a discrete, provenance-labelled line.

Colour reference: living Thumbi West Island fish at malawi.si →

About the species

Petrotilapia nigra is a rock-dwelling cichlid (an mbuna) found only along a stretch of the rocky southwestern shore of Lake Malawi, where dark, blue-black breeding males hold territory among the boulders. Like all members of its genus, it carries broad, fleshy lips packed with rows of long, flexible, mostly tricuspid teeth that it uses like a comb to graze the algal turf coating submerged rock. It is one of the lake's many narrow-range endemics: very common where it lives, but living nowhere else.

Full Petrotilapia nigra account →

Sources

  1. malawi.si — Petrotilapia nigra "Thumbi West Island"
  2. Eschmeyer's Catalog of Fishes — Petrotilapia nigra (species record)
  3. FishBase — Petrotilapia nigra summary
  4. FishBase — Petrotilapia pyroscelos (genus diagnostic comparisons incl. P. nigra)
  5. Marsh, A.C. 1983 — A taxonomic study of the fish genus Petrotilapia (Ichthyological Bulletin 48)
  6. Sabo, Konings & Stauffer 2026 — Petrotilapia kitrinos, a previously undescribed cichlid from Lake Malawi (European Journal of Zoology)