Taxonomy & naming
Hora described this species in 1932 in the genus Homaloptera; it is now placed in Homalopteroides (the combination is why the authority is in parentheses). The type locality is the Tadi Stream and Klong Pong at Ban Kiriwong, Nakhon Si Thammarat, Thailand. The Catalog of Fishes (Eschmeyer, CAS) is the authority for the valid name. The family is Balitoridae.
Morphology
Like its relatives it is a slender, flattened hillstream loach with broad paired fins held against the substrate. FishBase gives a maximum of 4 in TL. A colour description has not been compiled here.
Habitat
FishBase says adults inhabit high-gradient streams over fast bedrock, cobble runs and rapids, while juveniles stay in slower stretches of gravel and among exposed tree roots. It lists the species as freshwater and demersal, from the Mekong and Chao Phraya basins and the Malay Peninsula, and reports it from the Maeklong basin. Measured water parameters have not been published.
Feeding
FishBase reports that it feeds on aquatic insect larvae, particularly dragonfly and damselfly larvae, in addition to the biofilm grazing typical of balitorids.
Mating
Courtship has not been described for this species.
Breeding
Spawning has not been described, in the wild or in captivity.
In the aquarium
Hillstream loaches are fish of fast, well-oxygenated, cool running water. Keeping one means a river-style tank with strong flow, clean water and a biofilm-covered rockscape. Because FishBase records it eating insect larvae, offer small live or frozen foods alongside biofilm. Temperature and pH figures have not been published for this species.
Conservation
The IUCN assessed Homalopteroides smithi as Least Concern in 2011, meaning it is not currently considered at risk. It is a hillstream fish, so siltation and stream modification are the likely pressures.