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Sonia Guinane, 1999
Cichlid Room Companion
Artykuły

The Madagascan Cichlid Genus Paretroplus (Bleeker, 1865)

By , 2000. image
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Klasyfikacja: Przegląd gatunków, Madagaskar.

Paretroplus maculatus

This genus of Malagasy cichlids, currently consists of seven different species, the conservation status of which varies considerably. Their closest relatives are the Etropines, which are to be found in India and Sri Lanka. Following the fragmentation of the huge continent, Gondwana, in the Southern Hemisphere about 120 million years ago, Indo-Madagascar separated from Africa. India and Madagascar remained joined together until approximately 65 million years ago when even more fragmentation isolated Madagascar and subsequently most the flora and fauna of this mini-continent is unique and not seen in any other parts of the world.

These Paretroplus species that are known locally as damba by the Madagascan fishermen, are deepbodied fishes and the largest, Paretroplus maromandia, can reach 35cms TL. Another feature of the genus is the large emarginate tail, which gives some of them the appearance of the marine Surgeon fishes. The similarity between Paretroplus polyactis and Etroplus suratensis cannot be disputed superficially, but from a scientific point view, the basic physiology of all Paretroplus species is apparently very different. Etroplus suratensis is a herbivore, whereas Etroplus maculatus and all seven Paretroplus species are omnivorous.

Although much of their habitat has been destroyed, the majority of the Paretroplus species are to be found in lakes and rivers in the northwest of Madagascar, but with numbers being very much reduced. The introduction of Tilapia and Snakeheads as food fish for the population has also had on adverse effect on the native fish population. At one time, Paretroplus, whose flesh is relished by the local people, could support large fish industries on both the east and west coast, but now that situation has completed changed. These days the majority of the fish caught by the fishermen are Tilapia and Paretroplus make up a very small percentage of the catch, if there are even any at all. This is an indication of just how critical the status of these and other fishes, not just cichlids, really is and is apparently getting worse all the time.

Paretroplus polyactis

Paretroplus polyactis (Bleeker, 1878). 25-30 cms. Type locality for this damba, whose Malagasy name is "Masoavotoaka" and means "eyes bloodshot from drinking rum", is found along most of the eastern coastal region. It inhabits lagoons and the lower reaches of the many rivers in the area, although has been found further inland. It is able to tolerate brackish water and water with an even slightly higher saline content. The status of this damba is relatively secure at the moment as the introduced species do not thrive in this environment and it is still able to support a local fishery industry. So far this fish has not not been successfully bred in captivity, despite attempts in both France and Florida.

Paretroplus maromandia

Paretroplus maromandia (Sparks & Reinthal, 1998). 30-35 cms. Type locality for the only recently discovered and described "red" damba is the Andranomalaza River, adjacent to Maromandia, in northwestern Madagascar. Other populations can also be found in Lake Andropongy and the Maevarano River. This species has not yet been bred in captivity, which is a great pity as it is thought to be the most attractive Paretroplus ever found. The conservation status of this fish is not known for certain, but because of the delicate balance of the environment where it is located, it should probably be considered to be vulnerable.

Paretroplus damii

Paretroplus dami (Bleeker, 1878). 25-35 cms. Type locality for this spectacular damba are the various crater lakes on the island of Nosy Be, which is situated off the northwest coast of Madagascar. It is also found on the Malagasy mainland at various locations in the northwest, Lake Andrapongy, the Anjingo River, the Ankofia basin and in some small lakes in the lower Manbanjeba drainage. Compared to some of the other damba species, it has a fairly extensive range, but with declining numbers, whereas Paretroplus dami is apparently becoming quite rare in its type locality on Nosy Be. The breeding colouration of this fish is extremely attractive, red along the front half of the body and black on the rear half in a bicolour pattern. Unfortunately, so far, this fish has not been successfully bred in captivity. Hopefully this situation will change so that this particular species, whose conservation status must be considered vulnerable, becomes available in the hobby to help maintain a continuous captive-breeding program.

Paretroplus maculatus

Paretroplus maculatus (Kiener & Mauge, 1966) 30 cms. At one time, this damba was widely distributed in the northwest region of Madagascar, but now is restricted to one large lake and possibly another two smaller ones. The largest lake, Lake Ravelobe, and the other two are located within the Ampijoroa Forestry Station. The conservation status of this species is extremely endangered and therefore makes a captive-breeding program an absolute neccessity. I am happy to be able to report that the Maculatus has been successfully bred on both sides of the Atlantic, in ponds in Florida and an aquarium spawning at Bolton Museum Aquarium. Bolton Aquarium, who are running a Madagascan Captive Breeding Program, succeeded in raising several fry, some of which are currently swimming around in one of our tanks. It must be hoped that this most attractive species continues to breed within the hobby.

Paretroplus petiti

Paretroplus petiti (Pellegrin, 1929). 25-30cms. This damba, known locally by the Madagascan fishermen of Lake Kinkony, as "Kotso", is another species that had an extensive range in the western area of Madagascar, but in recent years has become very restricted. It is only to be found in one large lake, Lake Kinkony and some smaller adjacent lakes, so its conservation status must be considered nearly as precarious as that of Paretroplus maculatus. It has been bred successfully in Florida in outside ponds, which must give some cause for optimism. Specimens are also being maintained in France, so a spawning there is a distinct possibilty. We currently have two wild-caught semi adult, obtained from France as well as three tank bred juveniles, purchased in the USA. Eventually, we hope to be able to put all these five fishes together and maybe let nature take its course.

Paretroplus kieneri

Paretroplus kieneri (Arnoult, 1960) 15-20 cms. Not only is this the smallest damba, but also had the widest range along the western regions of Madagascar. It is to be found in both lakes and rivers, but like the other species in the genus in greatly reduced numbers. It is present in Lake Kinkony, alongside Paretroplus petiti, smaller lakes in the Betsiboka drainage as well as the Kalamilotra and Mangarahara rivers. The local name for this fish used by the fishermen of Lake Kinkony, is "Kotsovato" which means stone coloured "Kotso". The conservation status of this fish is not as acute as that of some of the other dambas and should not be considered too vulnerable, but as always with the existing native Malagasy habitats, there is an ultimate risk of deterioration. This species is very tolerant of varying water conditions and is the first of the genus to have been bred in captivity in France, Florida and also at Bolton Museum Aquarium in the UK. We have also recently had a successful spawning and the fry are now free swimming. It must be hoped that this attractive fish eventually becomes more available in the hobby.

Paretroplus menarambo

Paretroplus menarambo (Allgayer, 1997) 25cms. This beautiful fish, also known as the pin-stripe damba, is now believed to be extinct in its natural habitat in Madagascar. It has only been collected from its type locality, Lake Saradrano and recent attempts to find the fish have been unsuccessful. Local fishermen have stated that the fish was found in other lakes in the same area at one time, but has not been seen for several years. Therefore its conservation status is extremely endangered, if not already extinct. Thankfully, there are still specimens being maintained and successfully bred on both sides of the Atlantic. Spawning has occurred in outdoor ponds in Florida as well as a tank spawning at Bolton Museum Aquarium. In spite of the very small gene base, it must be hoped that these captive breeding successes continue. We have seven juvenile Paretroplus menarambo, six from Bolton and a single fish given to us by a friend in the States. This is one species that Dave and I are determined to breed when they are big enough, but like the rest of the dambas, they are very slow growing so patience is a must.

Most of the breeding successes with the Madagascan dambas have occurred in outside ponds in both France and Florida, with Bolton Museum Aquarium, (and now us!) achieving this within their tanks. According to the local fishermen, the breeding season for these fishes is believed to be restricted to the latter half of the rainy season, but this cannot be confirmed. It is known that they are substrate spawners with both parents sharing the care of the fry like their Central American cichlid cousins. The preferred spawning sites are probably on sunken pieces of wood, although in captivity other locations have apparently been used, rocks, flower pots and even artifical caves. (Our Paretroplus kieneri used a ceramic tube). The tendency for most Madagascan cichlids in captivity to eat their eggs does not really help their extremely endangered status, so artificial hatching of the eggs from a successful spawning is probably an absolute neccessity.

Thankfully, captive breeding programs for these fishes are happening and it must be stressed what an important part they are all playing to ensure that this genus of fishes, particularly the Paretroplus menarambo, has a future even with such extreme limitations.

Literatura (1):

Cytat

Guinane, Sonia. (cze 04, 2000). "The Madagascan Cichlid Genus Paretroplus (Bleeker, 1865)". Cichlid Room Companion. Źródło: na kwi 17, 2024, od: https://cichlidae.com/article.php?id=136&lang=pl.