Metriaclima sciasma
The scientific name of this fish species is Metriaclima sciasma. The species was first described by Patrick J. Ciccotto, Adrianus Konings and Jay R. Stauffer Jr. in 2011. The genus name Metriaclima is derived from the Greek: “metria” (average or inconspicuous) and “clima” (slope), referring to the moderate slope of the skull in this species. The species name sciasma is also from Greek and means “shadow”, a reference to the black pelvic fins of the males.
Prior to the official description, the species was already known by a number of temporary names:
- Pseudotropheus ‘Zebra Slim’
- Pseudotropheus sp. ‘kingsizei north’
- Maylandia ‘Zebra Slim’
- Metriaclima sp. ‘aurora north’
You can still find those names in books and magazines from before 2011.
Description
Metriaclima sciasma has a streamlined body, typical of mbuna cichlids. The head is usually light blue to grey-blue, depending on the sex and mood. The flanks of the males show 7-8 dark, horizontal bands on a light blue background. Females and juveniles are predominantly silver-grey with light blue marbling and yellow fin edges. The fins of the males are often blue, with black pelvic fins as a characteristic detail. The fins of the females are more yellow-brown to grey-brown. Males grow up to 8-9 cm in the wild, but can reach up to 12 cm in aquariums. In the wild, the amount of available food is limited. In the aquarium, they are often given too much and too strong food, which makes them grow larger. Females remain slightly smaller.
Differences between males and females: Males are considerably more colorful than females, with the characteristic blue color and dark bands. Females are much less conspicuously colored. Behavioral differences are most visible during reproduction. Juveniles closely resemble females in color and pattern.
Behavior and Temperament: Metriaclima sciasma is an active, bottom-dwelling fish. It is relatively peaceful within its own species but can be territorial towards other mbuna species, especially during the breeding season. It usually lives in small groups or pairs.
Life expectancy: The life expectancy of fish in the wild is unknown, but they can live 5-7 years in an aquarium.
Biotope
Metriaclima sciasma is native to Tanzania, in the northeastern part of Lake Malawi. They live in Lake Malawi, specifically in the transition zone between sandy bottoms and rocky areas at a depth of 7 to 20 meters.
Their natural habitat is characterized by a rocky bottom with sandy areas, with a moderate amount of algae and biofilms on the rocks. The banks are probably not densely covered with trees.
Metriaclima sciasma lives in a tropical climate, with stable water temperatures and no extreme seasonal influences such as floods or droughts.
Diet
In the wild, Metriaclima sciasma feeds primarily on algae and biofilms (aufwuchs) growing on rocks.
In the aquarium they can be fed a varied diet, with a high proportion of vegetable material. Suitable are for example spirulina flakes, algae wafers, and special mbuna granules with many vegetable components. Frozen food such as daphnia and artemia can also be offered, but to a lesser extent.
It is advisable to avoid foods high in animal protein as this can lead to long-term health problems.
The Aquarium
For a harem Metriaclima sciasma an aquarium of at least 120 centimeters in length is required. For multiple harems a considerably larger aquarium is required, for example 180 centimeters or more.
The setup should be rocky, with plenty of hiding places between the rocks. Plants are not essential, but can be added if the fish don’t eat them. A sandy bottom is best.
The ideal water parameters are a pH of 7.5-8.5 and a temperature of 22 – 26 °C.
Suitable tankmates include other peaceful mbuna species with similar requirements, such as certain Pseudotropheus species, but make sure there is enough space and hiding places to prevent conflict. Aggressive species or similarly colored species should be avoided.
Breeding aquarium and conditioning
Metriaclima sciasma does not need a special breeding aquarium. Because it is a mouthbrooder, the female protects the eggs until the young fish are released. There are also no special requirements regarding food.
The Spawn
The males of Metriaclima sciasma are always looking for females who want to mate. The courtship ritual begins as soon as a female shows she is willing. The colors of the male become brighter. He searches for the female and swims in front of her. He spreads his fins wide. With trembling movements he tries to lure the female to the place where he wants to spawn. This is usually a place on the sand under a rock.
Circling each other, the female lays an egg in the sand. While they continue to rotate, the male fertilizes the eggs. The female takes the eggs in her mouth. This continues until all the eggs have been laid and picked up by the female. The male’s task is now done. The female hides between the rocks to hatch the eggs.
Raising the fry
The eggs of Metriaclima sciasma hatch after 3 to 4 days. However, the female does not release the eggs yet. The young fish still live on their yolk sac, which allows them to continue growing. Only about 21 days after the eggs have been laid is when the female releases the young fish, usually near some rocks.
In an aquarium with many other adult fish, the young fish are a tasty snack. Because of this, many fish do not survive the first few minutes.
If you want to raise larger numbers of this species, catch the female after day 17. Place her in a rearing tank with the same water parameters as the main tank. A few rocks and some sand on the bottom will give the female a hiding place and the last few days to brood the eggs.
Once she is ready, the female will release the fry. She will not eat the fry for a few hours after releasing them. This will give you plenty of time to return the female to the main aquarium.
Particularities
Metriaclima sciasma is a relatively recently described species; much remains unknown about their behavior and ecology in the wild. The species is endemic to Lake Malawi and occurs in a specific part of the lake, indicating a high degree of specialization. The black pelvic fins of the males are a striking feature.
Conclusion
Metriaclima sciasma is relatively easy to keep for experienced Malawi cichlid enthusiasts. A spacious aquarium with suitable rocky decor and stable water parameters is essential. Their peaceful nature within their own species makes them suitable for a community tank, but careful tank mate selection is important to avoid conflict. The striking colors of the males make them an attractive addition to a Malawi aquarium.
Author
John de Lange
Copyright images
Mark Thomas – Marks Fiskenarie
