Trematocranus placodon "Ruarwe"

Ruarweroo-AH-rweh (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 Trematocranus placodon account →

Specific to Ruarwe

  • 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 Trematocranus placodon.

IUCNLEAST CONCERN · 2019
CARESNOT LISTED
Scientific size9.8 in25 cm total length
Temperature75–82 °F24–28 °C
pH7.7–8.8alkaline
Depth16–105 ft5–32 m
DietMolluscivore (crushes snails with pharyngeal teeth)
BreedingMaternal mouthbrooderUp to ~100 eggs
Sexual dimorphismYesBreeding males larger and metallic blue with darker barring and egg-spotted anal fin; females and non-breeding fish silvery with faint vertical bars.
PhotographsSee photosGoogle Images →

The Ruarwe population

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

Colour reference: living Ruarwe fish at malawi.si

About the species

Trematocranus placodon, the snail-crusher hap, is a sand-dwelling cichlid of Lake Malawi and its outflow waters that earns its name with a set of flat, paving-stone teeth on its throat bones, used to grind open lake snails. That same specialization makes it more than a curiosity: by cropping the snails that carry human schistosomiasis, the fish sits at an unusual intersection of cichlid ecology and public health. It is a big, handsome haplochromine that males turn out in metallic blues to spawn over broad sand craters they sculpt by mouth.

Full Trematocranus placodon account →

Sources

  1. malawi.si — Trematocranus placodon "Ruarwe"
  2. Eschmeyer's Catalog of Fishes — Trematocranus placodon (Regan 1922)
  3. FishBase — Trematocranus placodon summary
  4. Malawi Cichlids (malawicichlids.com) — Trematocranus placodon
  5. Madsen, Kamanga, Stauffer & Likongwe (2010), Biology of the Molluscivorous Fish Trematocranus placodon, Journal of Freshwater Ecology 25:449-455
  6. Chiotha, McKaye & Stauffer (1991), Prey handling in Trematocranus placodon — abstract