Home - aquarium - Aquarium Fish - Rainbowfish

Rainbowfish

RainbowfishesEvery seasoned aquarist has probably seen — or even maintained — the familiar Madagascar Rainbowfish, which is a staple at most local pet shops. That this fish is persistently called Bedotia, although for some years it has been clear that it is actually Bedotia madagascariensis, is irrelevant. Much more interesting is the fact that there have been more Bedotia species discovered and imported in recent years. Some of them haven’t yet been successfully established in the aquarium hobby.

For over 15 years, I have mainly worked with the rainbowfishes of Australia and New Guinea. I have kept many species and have also propagated them to some extent. Of course, some Bedotia madagascariensis found their way into my aquariums, but they led a rather shadowy existence. This species has been present in the aquarium trade since the early 1950s.

Toward the end of 2003, when I noticed two completely unfamiliar Bedotia species being offered on a U.S. auction website as Bedotia sp. “Ankavia” and B. sp. “Lazana,” I knew that somehow, I had to get some of these animals! I contacted the seller, Eric Bodrock of All Oddball Aquatics, and we thought long and hard about how we could get these fishes across the Atlantic. By a fortunate coincidence, I had to go on a professional trip to New Orleans in March 2004. Eric arranged the shipment of some animals to Louisiana, and I was soon flying back to Berlin with three pairs of each species in my luggage. I was in heaven!

New importsAUSTRALIAN_RAINBOWFISH

From that day on there was no stopping me. I began a correspondence with the Denver Zoo’s Alex Saunders, who had participated in some expeditions to Madagascar with Dr. Paul V. Loiselle. They had discovered many new species and brought some back to the United States. I also was in contact with other Madagascar fish fans, and even joined a Yahoo mailing list with the wonderful name “Madfish.” On my next trip to the United States in 2005, this time to Denver, Alex handed me fishes of five other species: Bedotia longianalis, B. marojejy, B. sp. “Lazana” (now described as B. leucopteron), B. sp. “Garassa,” and B. sp. “Namorona.”

At that time, passengers were allowed to take liquids in their carry-on luggage, but customs officials at the Denver and Berlin airports were amazed when I opened my bags! Luckily, I had an official export and import permit and a veterinary certificate for every animal. In the following months and years, I went to work nurturing and breeding these beautiful fishes.

Not all of my attempts were successful, even when I distributed offspring to zoos in Berlin, Brussels, and Cologne, as well as to professional breeders in Germany and England. This showed, unfortunately, that the “Bedotia wave» (if it ever existed) was short-lived. Since then, two species (B. marojejy and B. leucopteron) have disappeared from European aquariums because of problems with reduced fertility — some were not even bred further. B. sp. “Garassa” could not be propagated at all; the only male that I had died shortly after our arrival in Berlin.

At this point, only B. longianalis, B. sp. “Ankavia,” and B. sp. “Namo-rona” are still available in Europe. and they are kept and propagated by very few hobbyists, so these populations are at risk of disappearing permanently. For example, a filter accident was enough to wipe out my entire stock of B. marojejy (except one female) overnight. This was an unforgivable and irreversible mistake: despite the numerous offspring that I had distributed, I could no longer find a single fish.

Apparently there are still B. sp. “Garassa” and B. leucopteron in the hands of U.S. breeders and hobbyists, but B. marojejy is kept and bred only in zoos there. The New York Aquarium has some specimens of undescribed species from the north and southeast of the island, which are under Paul Loiselle’s care, but they have not been distributed further.

Environmental degradation threats

The Bedotiidae have many similarities to the Melanotaeniidae, and some researchers include both families in the suborder fishes — together with Telmatherinidae and Pseudomugilidae (blue-eyes).

Their location areas are far apart, but these fishes have one thing in common: they all originated from the supercontinent of Gondwana several million years ago. It is postulated that the rainbowfishes and blue-eyes descended from the marine Atheriniformes, also known as silversides. However, some believe that their evolution took place on Gondwana — hence in fresh water — a long, long time ago. So far, no fossil rainbowfishes have been found to support either hypothesis. What seems certain is that the vast majority of rainbowfishes and blue-eyes cannot live permanently in brackish water, contrary to information in the older literature. This is also true of the Malagasy representatives.

Bedotiidae (with the exception of a Rheocles species) are found only on the east coast of Madagascar, from the city of Henandrano (Fort Dauphin, in the far south) to the Mahanara River, near the northern tip of the island. They colonize all suitable habitats up to an altitude of about 2,625 feet (800 m). In some river systems, two species occur, but these are separated by an altitude boundary. Most of the populated habitats contain flowing water, but these species sometimes inhabit lagoons, manmade channels, and even rice fields.

Like all freshwater fishes of Madagascar, most Bedotia species are extremely threatened by environmental degradation, and this is compounded by the unstable political and economic situation in that island nation and the establishment of exotic species. Tilapia, Anabas, Channa, Gambusia, and Guppies endanger the native species, while many populations (if not species) have already disappeared from local waters. For years, no fishes have been exported from Madagascar (at least legally), so all species still kept in the hobby must be maintained and propagated. This also applies to the Malagasy cichlids and killifishes.

At least 16 other species are still awaiting description, although some of them have been known for over 20 years. One example is B. sp. “Namorona,” from the river of the same name in the Ranomafana National Park, in the southeast of the island.

Bedotia sp. “Namorona”Namorona

One of the most spectacular new species that have found their way to Europe is a still-undescribed species from the Namorona River system, which is largely in the Ranomafana National Park. Known as Bedotia sp. “Namorona” or the Sailfin Rainbowfish, this species was discovered in the early 1990s by Dr. Jürgen Clasen, who brought it to Germany. Unfortunately, it was not successfully established in the aquarium hobby.

Other researchers, including Patrick de Rham, Melanie Stiassny, Paul Loiselle, and Alex Saunders, were also able to collect the Sailfin Rainbowfish, and in 1998, Loiselle and Saunders successfully exported it to the United States. They collected a few specimens on the border of the Ranomafana National Park, in a stream called Ambatoharana just outside the city of Rano-mafana (approximately 21° 10 S, 47° 30 E) at an altitude of 1,560 feet (475 m). Subsequently, these specimens were successfully propagated at the Denver Zoo and the New York Aquarium and, to a limited extent, given into private hands. Animals brought to Germany in 2005 descended from these specimens. Their natural habitat consists of fast-flowing creeks and rivers, some of which are characterized by whitewater. The fish stay primarily in the quieter areas and wait for insects that fall on the surface.

Bedotia sp. “Namorona” is probably one of the most attractive species Madagascar has to offer. It is closely related to other species from the southeast, such as B. tricolor (which also has sail-like unpaired fins), B. geayi, and B. madagascariensis. Adult males reach about 4 inches (10 cm) standard length (SL), while females reach about 3 inches (8 cm) SL. Sexually mature males have very long, flag-like unpaired fins, which are deep black, red, and yellow patterned. No two males look alike! The caudal fin is smoky black in color, with yellowish-silvery elements. The body base color is a light yellow to beige, which is illuminated by a blue sheen on the back. A dark longitudinal band runs from the snout tip to the tail fin.

The females are beige and have a dark longitudinal band, bordered on the upper side by a greenish to golden row of scales. Their fins have a smoky border and sometimes show some red tones.

Like their relatives from Australia and New Guinea, Bedotia appreciate large planted tanks, which should also have a strong current. They can be described as omnivorous, but clearly prefer hearty live and frozen foods. Regular water changes (30-50 percent per week) are a prerequisite for good health and vitality. Despite their size, these are very peaceful animals that can be mixed with similarly sized species, such as smaller cichlids or other rainbowfishes. Males display for hours and spread their fins very wide—a breathtaking sight!

The breeding of B. sp. “Namorona” is relatively simple and very productive compared to other Bedotia, although some breeders have found a surplus of males among the offspring. Perhaps this is dependent on temperature or water quality. In normal Berlin tap water (medium hard and slightly alkaline), the sex ratio was approximately balanced at temperatures of 73-77°F (23-25°C). For breeding, a sufficiently large (31 inches/80 cm), well-structured tank should be provided, in which a trio should be set up for about a week. They spawn in Java Moss or artificial spawning mops, and the adult fish do not eat their eggs if they are well fed. It is advisable to condition the animals before breeding with plenty of live food. Once the first juveniles appear under the surface, the adult animals should be removed.

Rearing is relatively simple, even though the larvae grow slowly. Initially, they stay close to the surface, but after a few days they start roaming throughout the tank. In the first weeks and months, the larvae and young fish are very sensitive to stress. Any tank maintenance should be done with caution. Water changes should be avoided for the first three to four weeks, as they stress the fry so much that losses result. Once the fry have reached a size of about 1.2 inches (3 cm), they are out of the woods.

Additional species

Besides B. sp. “Namorona,” small populations of B. sp. “Ankavia” and B. longianalis are still kept and bred in Germany by a handful of members of the International Rainbowfish Association

(IRG). Although these two species come from quite different regions, the above suggestions regarding care and reproduction apply to them, too.

Bedotia sp. “Ankavia” is a very nice species, but its beauty takes some time to unfold. Adult males are metallic blue to turquoise and have reddish fins. The females are golden and carry a prominent black longitudinal band. The animals come from the Ankavia-Anka-vanana system, which is located in the northeast of the island near Andapa. The area is intensively farmed for vanilla cultivation and the last remnants of rainforest are gradually disappearing, but at this point the rainbowfish populations appear safe.

Bedotia longianalis is found along the east coast, between the city of Toamasina (Tamatave) and Antongil Bay. It replaces B. madagascariensis to the north. Various locality forms have become known; the animals kept in Europe probably originated from the Menantany stream. This type is not as colorful as the other known species. It shows more subtle beige, sky-blue to lavender, and gold tones, and the fins are yellowish to orange. These animals are subject to stress when kept with larger or very active fishes. Sometimes the fish heals by itself, but usually the disease is fatal, despite some limited success with medications that are used to fight Hexamita or Spironucleus.

It would be wonderful if more aquarists would dedicate themselves to the breeding and conservation of these species in the hobby, especially within the IRG. Further imports to Germany are unlikely, even from the U.S., where additional species are still kept, and the destruction of nature in Madagascar continues. There is a small community of researchers who work with the fishes of Madagascar and their preservation, but their efforts have a limited impact, given the magnitude of the task. Still, some small accomplishments have been achieved; recently, for example, the habitat area of B. Makira region was put under protection. And for the first time, explicit measures have been taken to protect the aquatic environment.

published by: Gillgallery.com

Read more:
Aquarium Fish

Leaved a comment to "Rainbowfish"

* Comment
*Required fields

Attention: All comments are moderated.