Taxonomy & naming
Tachysurus trilineatus (Zheng, 1979) is the valid name in the Catalog of Fishes, originally described in another genus. The store sold it as Pseudobagrus trilineatus, the older genus placement; Tachysurus is the genus the Catalog of Fishes uses for the East Asian species formerly in Pseudobagrus. The type locality is a mountain stream in Luofu Shan, Boluo County, Guangdong. The epithet is Latin for 'three-lined'.
Morphology
It is a small East Asian bagrid with four pairs of barbels, an adipose fin and spines in the dorsal and pectoral fins, and a pattern of three lines suggested by its name. FishBase gives a maximum of 3 in SL.
Habitat
FishBase says it is endemic to the Dong Jiang drainage in Guangdong Province, China, and lists it as a freshwater, benthopelagic subtropical fish. It was described from a mountain stream in the Luofu Mountains.
Feeding
Diet is not recorded in the sources available to the atlas. Small bagrids of this kind eat insect larvae, crustaceans and small fish at night, and in captivity take frozen and live foods.
Mating
Mating behaviour is not recorded in the sources available to the atlas.
Breeding
Captive breeding of this species is not recorded in the sources available to the atlas.
In the aquarium
Offer cool-to-moderate clean water with good oxygenation, caves and stones, and peaceful tankmates too large to be eaten. FishBase calls it subtropical and gives no temperature, pH or hardness range.
Conservation
The IUCN Red List assessed it as Least Concern in 2024, meaning it is not considered at risk of extinction at present. It is endemic to a single river drainage.