Date: Sun, 25 Oct 1998
From: Hans Beiderbeck (habei@gmx.de)
One thing about the identification of the species. On your site there are two Latin names given for a fish called the weather loach: Misgurnus anguillicaudatus and M. fossilis. One reader even mentions that Cobitis taenia is sold as the weather loach. The latter is easily distinguished from the Misgurnus species (at least if you catch him sleeping) since the genus Cobitis carries only 3 pairs of barbels whereas Misgurnus carries 5. The Cobitis also stays much smaller (ca. 14 cm) than the Misgurnus (up to 30 cm).
The two Misgurnus species can be distinguished by their color pattern. The M. anguillicaudatus displays lots of small spots, whereas the M. fossilis shows bands from the tail to the head, with no or only few spots. Therefore all the pictures of weather loaches on your site show M. anguillicaudatus. This is also more likely because of another reason: M. fossilis is a native species of Europe. In most parts of Western Europe, however, it is a very rare species (In Germany it is even close to
extinction). As far as I know that's a different story in Eastern Europe (Hungary, Romania), but I'm not sure how many aquarium fish are exported from there to the U.S.. The M. anguillicaudatus is a native of China, Korea and Japan and doesn't seem to be endangered. The golden Dojo is probably a golden form from one of the Misgurnus species and it's more likely that it's from M. anguillicaudatus, too.
Recently I found two photos of the real M. fossilis (
Kaltwasser Fische and
http://www.icf.de/UISonline/dua96/html/fische01.htm), but they are very poor. However, I also found an excellent drawing of M. fossilis here:
http://clinicom.uhc.lublin.pl/mazury/ryby/piskorz.htm.
Now how to keep and breed them: The following is a short summary of an article published in the largest aquarium newspaper in Germany. The citation is Hartl, A. (1991), Die Gattung Misgurnus, D. Aqu. u. Terr. Z. (DATZ) 44:760-762. Even though it is in German, I recommend getting the original article for all Dojo enthusiasts because of its good pictures of both Misgurnus species. The most important thing to know about keeping M. anguillicaudatus is that this is not a tropical but a cold water fish, even though they can stand high temperatures very well. The author got his pair from a garden pond where they lived over a German winter, even surviving frost. A cold period of several months might be essential if you want to breed them, because at constantly high temperatures they might not become fertile. In May, at water temperatures of 24 C they started to spawn. The pair glides side by side through the tank finally spawning close to the surface of the water. The whole process takes up to 4 hours. After that the parents should be removed. After three days the fry were fed by protozoa and after 10 days they started to take artemia. A month later the largest of the fry were 25 mm long.
The sexes can be distinguished by the pectoral fins. The pectoral fins of the male are much larger than the females'. Also, the first two spines of the male's pectoral fin are much stronger than the rest. It seems to be worth mentioning that the author bred a pair of golden Dojos but all of the young had the light brown color with dark spots of the wild form.
Last, but not least, I'd like to give an important message, especially to European readers: Depending on which part of China your individual M. anguillicaudatus originate from, it is very likely that they are able to survive European winters. Therefore you shouldn't release them into the wild because they might crossbreed with the native M. fossilis further hurting populations of this endangered species. The same goes for garden ponds, since M. anguillicaudatus, under humid weather conditions, is able to leave them and escape into the wild. Keep your aquariums tight, too.. ;-).
Hans
Read that! yeah its long but it basically explains sexing
