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Haplochromis cyaneus
by Greg Steeves

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Conditions must have been favorable for these fry have developed into wonderful aquarium tenants. As the have progressed to sexually active juveniles (pictured below), some curious features have presented themselves. The first distinctive characteristic we observed was a thin solid, somewhat thin midlateral line dissecting the body vertically. This same trait is seen on other species from the region including Ptyochromis sp. "salmon", Platytaeniodus sp. "red tail sheller" and 'Haplochromis' sp. "Kenya gold". These former fish are all mollusk eaters. Could it be possible that Haplochromis cyaneus shared a common ancestor with some of these snail eaters and developed the rock picking method of feeding to fill a niche? This one characteristic might in itself not be enough to sustain this idea, but a close look at the head and jaw structure may just lend itself to further support a common "rockpicker-sheller ancestral tie" theory. Shelling species have a steeply inclined cranial profile. This is present in both 'H.' cyaneus and 'H'. flavus. Admittedly, this steep cranial slope at the nuchal region is not limited to only shelling species, but is especially prevalent in this assemblage. The mouth of 'H' cyaneus is small when compared to all other lineages of haplochromines except for many shellers (Ptyochromis, Platytaeniodus etc.). The upper and lower jaw forms a formidable appendage very similar in structure as to what we see in the molluscivores. The similarity of physical attributes is undeniable. It would be of immense interest to distinguish the placement of the noted fishes on a phylogenic tree. This hypothesis warrants further study. Perhaps molecular data will further verify this relationship.

Water Fin Underwater Fish Marine biology


At Makobe Island, 'Haplochromis' cyaneus is a resident of the surf zone in shallow water. Here it flows in the in the rolling waves while picking at the algal growth along the rocky bed. In our aquatic arrangement, it was unnecessary to provide strong water movement to simulate tidal action and the substrate was fine grain sand, a sharp contrast to its natural habitat. This was of no consequence to the fish that continuously forage though the sand strata looking for edible bits. In all probability, 'H' cyaneus has adapted to this rather hostile niche at Makobe Island to escape the aggression of other more intimidating inhabitants. This fish has a mild disposition and would undoubtedly not last long with other residences of this location such as the beautiful Pundamilia nyererei. In terms of temperament, one should expect a similar character to the shelling species mentioned above.

In observations concerning spawning behavior, a rather typical haplochromine sequence of events transpires. The initial trigger that transforms an individual from the typical juvenile or female-like coloration to the radiant majesty of a dominant hues is generally the maturation of a female; her becoming gravid. The male will alter between shaking to the female and chasing off any trespassers while establishing a loose territory. It is at this time that male coloration in most intense. He digs a small pit in the sand which seems in sharp contrast to what he may be able to do in native waters (over a hard rock substrate). The female eventually reacts positively to his efforts and accepts his spawning location. They circle each other, the female dropping eggs and nipping at the egg dummies on the males anal fin. aquariums.

It is at this time that the male releases milt and fertilization occurs. After the female has spent her compliment of eggs and is gently turning them in her buccal cavity, she swims off to incubate her clutch in relative peacefulness. The male quickly loses interest in the female and returns to foraging. The female will hold her brood for 14 days at 29C. Warmer temperatures will hasten the incubation process while lower temperatures will extend it. In the aquarium, the female will tend her brood for a further two weeks after which time they are weaned away from her and left to fend for themselves. In a species only aquarium, it is common for a few fry from each brood to survive. Brood sizes number as high as 30 young.

If a haplochromine community tank is to include 'Haplochromis' cyaneus, one should avoid the sheller species mentioned earlier which have similar markings (especially the females) as well as more aggressive species. A good practice to abide by is to provide as large an aquarium as possible for your colony. Although growth and breeding is possible in a tank of 80 liters, a larger aquarium of 200 liters or more is recommended so one may observe a more relaxed and presumably natural behavior.

'Haplochromis' cyaneus is included on the IUCN Red List as endangered with a decreasing population trend as well as appearing on the CARES Preservation List.We have been informed that captive stocks in Europe have dwindled.In the USA we now have an organized group of people dedicated to the preservation of endangered species. Efforts are well underwayto ensure that healthy captive populations will produce enough fry to ensure 'Haplochromis' cyaneus exists in our aquaria, for many years to come.
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References:

Bohner, Axel; 2010; Die Viktoriasee-Cichliden in Deutschland; pp. 28-29.

Seehausen, Ole & E. Lippitsch, N. Bouton and H. Zwennes; 1998; "Mbipi, the rock-dwelling cichlids of Lake Victoria: description of three new genera and fifteen new species";Ichthyological Explorations of Freshwaters; pp. 129-228.

Seehausen, Ole; 1996; "Lake Victoria Rock Cichlids"; Verduyn Cichlids; pp. 146-158.

Seehausen, Ole & N. Bouton; 1998 The Community of Rock-Dwelling Cichlid in Lake Victoria http://www.zfmk.de/BZB/ B47_H3_4/BZBB4715.PDF

Steeves, Greg & Hansen, D, and Lamboj, A. 2010; Cichlids of Africa Vol I Haplochromines. Granda Publishing.

Originally published in The Lateral Line, the official publication of the Hill Country Cichlid Club.
 
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