Aquarist Atlas
↑ Collection form of Petrochromis ephippium

Petrochromis ephippium "Udachi"

Udachi — oo-DAH-chee (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 Petrochromis ephippium account →

Specific to Udachi

  • 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 Petrochromis ephippium.

IUCNLEAST CONCERN · 2025
CARESNOT LISTED
Scientific size7.9 in20 cm total length
Temperature75–82 °F24–28 °C
pH8.6–9alkaline
Depth0–16 ft0–5 m
DietHerbivore; scrapes aufwuchs (diatoms and filamentous algae) from sunlit rocky surfaces using tricuspid dental combs
Breedingmaternal mouthbrooderSmall clutches typical of large Petrochromis; dominant males polygamous
Sexual dimorphismYesDominant males grow largest and color up most intensely; sub-dominant males and females can appear similar at a glance
PhotographsSee photosGoogle Images →

The Udachi population

Petrochromis ephippium "Udachi" is the Udachi population of Petrochromis ephippium, 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 Petrochromis ephippium, distinguished by its collection locality and local coloration; aquarists keep and breed it as a discrete, provenance-labelled line.

Colour reference: living Udachi fish at tanganyika.si →

About the species

Petrochromis ephippium is a robust, algae-grazing cichlid endemic to Lake Tanganyika, where it works the shallow tumble of rocks just below the surface, combing a living film of diatoms and filamentous algae off stone with rows of fine tricuspid teeth. Its species name means "saddle" in Latin, a nod to the pale, roughly rectangular patch many fish carry beneath the dorsal fin. To hobbyists it usually arrives under the trade tag "Petrochromis sp. Moshi" or "Moshi Yellow" — a big, pugnacious, fast-moving fish that demands a long tank and a keeper who understands its herbivorous gut.

Full Petrochromis ephippium account →

Sources

  1. tanganyika.si — Petrochromis ephippium "Udachi"
  2. FishBase — Petrochromis ephippium summary
  3. Eschmeyer's Catalog of Fishes (Cal. Academy of Sciences)
  4. GBIF — Petrochromis ephippium
  5. Mattsson, C. (2018) — A morphological and molecular analysis of the species diversity of the cichlid genus Petrochromis from Lake Tanganyika (bioRxiv 280263)
  6. Yamaoka — Feeding behaviour and dental morphology of algae-scraping cichlids in Lake Tanganyika (African Study Monographs)