Gecko Loach

About

Found in the fast-flowing waters of Thailand's Chao Phraya basin, Pseudohomaloptera sexmaculata is a small hillstream loach that most people encounter as an accidental addition to a shipment of something else. When a common name gets applied at all, it is usually 'gecko' or 'lizard' loach, and the nicknames are well earned. The body is flattened top to bottom, the paired fins splay out horizontally like limbs, and the whole undersurface acts as a powerful suction cup. Rather than swimming freely, these fish crawl and hop from rock to rock in a way that looks almost reptilian. A series of dark saddle-shaped markings runs along the back, which is typical of the group. The taxonomy here has been shuffled around considerably over the decades. The species has passed through Homaloptera, Balitoropsis, and finally into Pseudohomaloptera, so older references may list it under different names. Despite the 'aggressive' tag sometimes applied, this fish is not particularly combative and does best in a group of four or more, with solitary individuals tending to fade. Tankmates should be chosen with care since it needs the same high-oxygen, brisk-current conditions that few community fish share. Breeding has not been documented in captivity.