Article © Shane Linder, uploaded January 01, 2002.
Perhaps a better title for this piece would be "Beauties and Beasts." In this article we look at what are not only some of the most beautiful fishes in the hobby, but also the hands-down meanest freshwater fishes known. The beauties belong to the genera Leiocassis/Pseudomystus and Bagrichthys, and the beasts to the genus Hemibagrus.
Before we get started, I want to spend a minute discussing taxonomy (don't skip the page!). To simply say that the family Bagridae "needs some taxonomic work" would be a gross understatement. I do the best job that I can researching the scientific literature in order to keep up to date on the latest taxonomic findings and changes. However, what do you do when there are glaring contradictions in the scientific literature? I bring this up now as these contradictions affect one of this article's subjects. In 1991 Mo, following Jayaram's previous findings (1968), divided Leiocassis into two genera (Leiocassis, eight species, and Pseudomystus, 13 species).
This change affects the hobby because two commonly imported bagrids, Leiocassis siamensis and L. stenomus were placed in Pseudomystus. The problem is that some authors that published after Mo's book have not used Pseudomystus and have kept referring to these fishes as Leiocassis. Since this series on bagrids follows mainly Mo's work, I will from now on use Pseudomystus and Leiocassis as defined by Mo. The reader should be aware though that some scientific literature on these species is still being published using the genus Leiocassis and that nearly all references in the hobby refer to these species as Leiocassis.
The genus Pseudomystus still needs some serious attention. In the past it has been used to group together nearly all of the "bumble bee-patterned" catfishes of Southeast Asia. The hobby has done the same in that all of these fishes are sold under the name "bumble bee catfish" and nearly always labeled Pseudomystus siamensis even though there is likely more than just this one species imported. Pseudomystus stenomus is usually found under the common name false bumble bee catfish.
The Pseudomystus "bumble bee catfishes" are all very beautiful. The body is a velvet black highlighted with bands of white or off-white. At least one species of Pseudomystus is known to lose its black coloration and turn pure white with age. These catfishes are nocturnal, but with a little patience, they can be conditioned to accept food when the aquarium lights are on. It is a good idea to condition nocturnal catfishes to do this because it is often the only time that you will see them and be able to observe their health. Pseudomystus, like some doradids, have a way of disappearing in a tank only to be found months later when you decide to re-aquascape the tank.
It is imperative that they are fed properly after lights out and not left to live off of only what they can scrounge up in the aquarium. The hobbyist should also be aware that they are efficient predators and will consume fishes up to half of their size. If your tank is missing a couple of tetras or barbs, the "bumble bee catfish" is almost certainly your culprit. These fishes do well in a community set up, but each individual will need its own cave as they can be quite territorial amongst their own kind. Aggression is displayed by biting another Pseudomystus' caudal fin. Damaged caudal fins are a sure sign that there are not enough retreats for all of the fish to live comfortably. All Pseudomystus can be sexed in the typical bagrid fashion and the males' genital papilla is even more distinct than in many other bagrids.
Both the "bumble bee" and "false bumble bee" can be found in creeks and rivers throughout Borneo, Thailand, Sumatra, Java, and Malaya. Although they come from normally soft acidic waters they can easily adapt to almost any water conditions provided the extremes are avoided.
The genus Bagrichthys hails from Borneo, Sumatra, Cambodia, and Thailand. This genus is known to the hobby primarily because of the black lancer (B. macracanthus). The genus presently contains four species. B. macracanthus, the only member of the genus imported, is truly one of the most beautiful fishes in our hobby. The fish is a solid velvet black with a white mid-axial streak that runs from the shoulder to the caudal peduncle. The entire caudal fin is a transparent white and develops flowing extensions with age. The lancer in "black lancer" refers to this fish's disproportionately tall dorsal fin which, when folded down, reaches nearly to the caudal peduncle. These fish can be expected to reach an adult standard length of about eight to ten inches but is slow growing and will require a few years to reach this length.
The black lancer is, by nature, very nocturnal. Once again though, with some conditioning, the fish can be taught to eat with the lights on and even to feed from its owner's hand. If the fish is kept in a community type tank be sure that it receives an adequate diet. Wild specimens have been caught with worms on a hook and line, but stomach contents also showed plant detritus. These fish are often territorial among their own kind, but as with most bagrids, aggression can be severely reduced by keeping one male with two or more females. Lancers are very adaptable to changes in pH and DH and will thrive as long as extremes are avoided. It has been suggested that raising the tank's temperature above 80F for a couple of days helps lancers to cope with the stress of being moved. The sexes are easy to distinguish. Not only does the male possess a genital papilla, but the males' nasal and maxillary barbels are more than twice as long as the females'.
Now that we have looked at the beauties, let's cover the beasts. Most of the larger "Mystus" catfishes were moved to the genus Hemibagrus by Mo in 1991. Two of these, the Asian redtail and the crystal-eyed catfish, Hemibagrus wyckii, are imported for the hobby with increasing frequency. The Asian redtail catfish is really a complex of closely related Hemibagrus species. A lot of work is currently being done with this genus, and as soon as this work is completed, we will know which species are being imported.
Asian redtails used to be quite rare and expensive in our hobby. However, many Asian countries have recently begun serious aquaculture programs aimed at keeping their country fed. The large Hemibagrus species have proven ideal for this and are now being farmed in many Asian nations. A byproduct has been that large numbers of young Hemibagrus are now showing up in the aquarium trade. Young Asian redtails in the two to three inch range are becoming a common sight in many pet stores. At this size, the fish's body is nearly black and the tail shows only red highlights. Against the black body, the long white barbels contrast nicely.
Most of these redtails will reach a maximum standard length of around two feet. It is not just their size that makes them beasts, but also their disposition. In nature, redtails over 12 inches are strictly predatory with other fishes accounting for nearly half of their diet. Crustacea and insects make up most of the remaining half. Barbs, three spot gouramis, and even snakeheads (Channa spp.) are all eaten along with many other fishes. One redtail was even found with the remains of a snake in its stomach. In captivity, specimens over four inches will need their own tank as they will not tolerate tankmates. Captive care is simple, just provide clean water with a good flow from a power head. A couple of large PVC pipes and rounded rocks provide hiding places and complete the set up. Water chemistry is of little concern since these fishes often hunt from the soft acidic waters up-river down to the brackish deltas of the larger Asian rivers.
The crystal-eyed catfish, Hemibagrus wyckii, is also quite striking. The entire fish is black with white markings on the caudal and dorsal fins. The eyes are a sky blue much like those of Panaque cochliodon. H. wyckii is capable of attacking animals of its own size. Dr. David Sands claims that it is the "only freshwater fish clearly unafraid of man". In captivity they will reach over two feet standard length and wild specimens have been reported at just under three. These fish have tremendous jaw strength. One aquarist reported that her specimen managed to bite, and nearly flatten, an aquarium heater protected by an aluminum sleeve. A proper set up for a crystal-eyed catfish should be similar to what has been recommended for Asian redtail catfishes. One major advantage that the Hemibagrus species have over the large South American catfishes is that they are less skittish in captivity.
This article would not be complete without mentioning the responsibility that a hobbyist incurs when they purchase one of these large predators. Give some serious thought to the long term care of these animals before you purchase one. Are you going to want to keep a 200 to 300 gallon aquarium with only one fish in it? Whether you prefer to keep the beauties or beasts of Bagridae, there is no doubt that this family has a lot to offer any aquarist. In the next page we will finish up the Asian bagrids with the genus "Mystus".
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