Congolese Barb (Raiamas sp.)

Aquarists should be quite familiar with danios and rasboras. These two groups feature dozens of common and uncommon aquarium species and represent one of the major branches of the minnow family Cyprinidae. They are classified as separate tribes, the Danionini and the Rasborini, but all the non-ichthyologists reading this might be surprised to learn that there’s also a third tribe out there which is seldom seen in captivity.

The Chedrini is the forgotten cousin of the danios and rasboras and includes 18 different genera found all across the tropical and subtropical freshwaters of the Old World. The Asian species in Barilius are probably the most commonly seen member within the aquarium trade, and, while they make for a beautiful and active addition, they’re still mostly a niche item. The Apollo Shark (Luciosoma setigerum) is another uncommon find from Asia, but little else from this group is encountered with any regularity.

The African chedrins belong to a separate subgroup, and recent study has shown that our understanding of their evolutionary history is still imperfectly known. These are often ecologically important within these aquatic ecosystems, as exemplified by the enormously abundant Lake Sardine (Engraulicypris sardella) from Malawi, which forms an important local fishery and is a prominent part of the diet for the lake’s larger predators. Of course, this fish isn’t a sardine, but, rather, a silvery minnow.

The one African chedrin that does occasionally find its way into aquariums is Raiamas, home to about 17 species presently; however, this genus is now understood to be comprised of several unrelated lineages that will eventually be split into new genera. For instance, the two Asian species are more closely related to other Asian chedrin genera, and the African species fall into at least three separate groups.

The species most commonly seen in aquarium exports is varyingly identified as R. christyi or R. ansorgii, though correct identification among these fishes is quite difficult. These are sometimes referred to as coppernose barbs thanks to a bright coppery spot present on the snout. Most members of this genus share a similar appearance, looking a bit like a giant danio crossed with a small trout. While there are a few Raiamas that grow fairly large (for instance, the two Asian species reach nearly a foot in length), most species are fully grown at 5-6 inches, and thus highly suitable for captivity.

With their energetic swimming, it is important to keep these shoaling fishes in large systems with plenty of open swimming room. An aquarium measuring 6 feet long would be ideal. A tight fitting lid is a necessity for these jumpy creatures, as even the smallest of opening is likely to be an irresistible exit point for a Raiamas. Groups of a half-dozen or more are highly recommended. Much like with danios and rasboras, nearly any food will be accepted readily.

For tankmates, it is wise to avoid any small and overly placid fishes. There are a few commonly seen groups from Africa’s rivers that present the opportunity to create a biotope: Congo Tetra, Distichodus, Synodontis, Steatochromis cichlids.