Apollo Shark

About

Found across fast-flowing, high-gradient rivers from Thailand to Sumatra and Borneo, this streamlined cyprinid, Luciosoma spilopleura, is one of the more fascinating cases of identity confusion in the freshwater hobby. Despite the name appearing regularly on stock lists for decades, the actual species may never have been collected for the aquarium trade at all. What's sold under this name is almost always a different Luciosoma species, typically marketed as an apollo shark or shark minnow with an incorrectly applied label. The true fish, as described from historical sources, has a moderately pointed head, a row of dark elongated spots along each flank, and a caudal fin marked with a central dark stripe and submarginal bands on both lobes, with greenish coloration above and silver below. In practice, Luciosoma as a group are active, fast-swimming surface and mid-column fish that need space and should be kept in groups. Crowding them into too small a tank invites aggression among themselves, and smaller tankmates may become targets. They're not a good fit for a peaceful community setup. For the right keeper with a large tank and a taste for active, schooling cyprinids, the genus is rewarding. But go in knowing that confirming which species you actually have is genuinely difficult.