Perissodus microlepis "Ulwile Island"
Ulwile Island — oo-LWEE-leh 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 Perissodus microlepis account →Specific to Ulwile 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 Perissodus microlepis.
The Ulwile Island population
Perissodus microlepis "Ulwile Island" is the Ulwile Island population of Perissodus microlepis, a geographic colour form from the Tanzania coast of Lake Tanganyika in the north-central part of the lake. It is the same species as Perissodus microlepis, distinguished by its collection locality and local coloration; aquarists keep and breed it as a discrete, provenance-labelled line.
Colour reference: living Ulwile Island fish at tanganyika.si →
About the species
Perissodus microlepis is a small cichlid from Lake Tanganyika that earns a living the way almost nothing else in fresh water does: it sneaks up behind larger fish and tears scales off their living flanks. Stranger still, the population comes in left- and right-mouthed forms, each twisted to bite one side of its prey — and a famous 1993 field study argued that whichever form is rarer enjoys a hunting advantage, keeping the two near a 50:50 split through frequency-dependent selection. That tidy 'textbook' story has since been complicated by work suggesting the asymmetry is more of a continuum than two clean morphs, which is part of what makes this unassuming fish one of the most argued-over animals in evolutionary biology.
Full Perissodus microlepis account →Sources
- tanganyika.si — Perissodus microlepis "Ulwile Island"
- Eschmeyer's Catalog of Fishes — Perissodus microlepis (species record, Boulenger 1898; holotype, synonymy)
- FishBase — Perissodus microlepis (size, ecology, trophic level, distribution, etymology)
- GBIF — Perissodus microlepis Boulenger, 1898 (taxonomy & occurrences)
- Hori, M. (1993), 'Frequency-Dependent Natural Selection in the Handedness of Scale-Eating Cichlid Fish', Science 260:216-219
- Hori (1993) abstract & metadata — PubMed