Petrochromis fasciolatus

Petrochromis fasciolatus

The genus name Petrochromis can be divided into two parts: Petro is derived from the Greek word Pete which means “rock” as a reference to the habitat of this family. Chromis is derived from Chroma which means “colour” and refers to the many colours of cichlids. Freely translated it says something like Rock fish. The species name fasciolatus comes from Latin and means “narrow stripes” in reference to the narrow vertical bands on the flanks of this species.

Description

Depending on the location, the Petrochromis fasciolatus has different color variants. From Ikola, the males have a red stripe above the eyes. The variant of Nkondwe is a bit more yellow in colour. The Petrochromis fasciolatus distinguishes itself in its physique by the far protruding lower jaw. As a result, the beak points slightly upwards whereas that of the other Petrochromis species points downwards.

The males grow to about 12 to 15 centimeters, the females remain somewhat smaller. As the name implies, they have more than 10 narrow vertical stripes on the flank. Two tires run over the head. The jaw is uniform in color.

Biotope

You can find the Petrochromis fasciolatus all over the lake. They inhabit the areas of the lake that are strewn with rocks in the transition zones where the Aufwuchs are covered with sand and detritus. They mainly occur at depths up to about 7 meters.

The males are rarely territorial. When they want to spawn, they defend a temporary spawning site in one of the deeper parts of their biotope at a depth of about 10 to 15 meters.

Diet

Petrochromis fasciolatus is a real herbivore. With their thick, fleshy lips studded with tiny teeth with a three-pointed crown, they scrape the algae off the rocks. Sometimes they school together in schools of 40 to 250 individuals to invade the territories of larger Petrochromis species and quickly eat the algae there. In many cases, these are Variabilichromis moorii territories. Should a Petrochromis fasciolatus attempt it alone, it would soon be chased away. In a large group, however, they overwhelm the defenders. The larger the group, the more often they gather and raid other territories.

They mainly feed on the smallest algae and diatoms. To do this, they press the lips against the rocks that form to the surface and close the lips. As a result, the teeth comb through the algae strands and the fish ingests the fine algae and diatoms. This Petrochomis species is a less specialized algae eater than the other Petrochromis species, they have much fewer teeth to comb through the algae strands. They compensate for this by snapping into the Aufwuchs faster and more often. Because they inhabit the transition zones where there is still a lot of sand in the Aufwuchs, they also digest a lot of sand.

Algae are very difficult to digest. This specialized algae eater has an adapted intestinal system which enables him to digest the algae well. Their intestinal tract is 10 times the length of the fish itself. This specialization prevents them from properly processing other foods. Therefore, do not give them meat-like food to prevent diseases. Instead, feed them a very high-quality vegetarian diet.

The Aquarium

Given the size of these fish and its aggressive behavior, it is advisable to keep them in a fairly large aquarium. Furnish it with a lot of sand and some big rock walls for aufwuchs to grow on. Keep them in a group where you have more males than females to spread the aggression between them. Also provide distraction in the form of other herbivorous robust species such as a group of Tropheus.

Breeding Petrochromis fasciolatus

Petrochromis fasciolatus is a maternal mouthbrooder. The male makes a pit in the sand at the bottom of a rock. Here he lures the female to spawn. The female takes the fertilized eggs into her mouth and incubates them in her mouth. She holds the fry as long as possible. After 4 to 8 weeks they no longer fit in her mouth and she releases the fry.

Conclusion

Petrochromis fasciolatus is a species that requires the necessary attention for its diet, combined with mutual aggression, it is a fish that should only be kept by experienced Tanganyika aquarium keepers.

Video

Author

John de Lange

Copyright images

Sue – Suephoto.com (original website no longer available)

Resources
Fishbase.org
Tanganyika.nl
Algeneters uit het Tanganyikameer Tropheus- en Petrochromis-soorten – Ad Konings – Cichlidae 27-2 April 2001 blz 39-48
Group foraging by herbivorous cichlid fish, Petrochromis fasciolatus, in Lake Tanganyika – Masanori Kohda & Yasuhiro Takemon