Taxonomy & naming
Sarcocheilichthys nigripinnis was described by Albert Günther in 1873 as Barbus nigripinnis, with Shanghai, China as type locality. The Catalog of Fishes gives it as Sarcocheilichthys nigripinnis (Günther, 1873) in Gobionidae. FishBase notes two subspecies: S. n. morii in Korea and S. n. nigripinnis in China and Taiwan.
Morphology
A compact gudgeon. FishBase gives a maximum of 6.5 in TL for males or unsexed fish. The epithet means black-finned, and the rainbow common name refers to the iridescent colour of breeding males.
Habitat
FishBase records the fish from China, Taiwan and Korea. It classes the species as benthopelagic and temperate. Water chemistry and microhabitat are not recorded.
Feeding
The diet is not recorded in the FishBase entry.
Mating
Courtship and spawning behaviour are not recorded in the FishBase entry.
Breeding
Fecundity, egg type and spawning season are not recorded in the FishBase entry.
In the aquarium
A hardy cool-water fish for native-style and unheated tanks. FishBase gives no temperature, pH or hardness range for it, so the atlas sets none. Keep a group over sand or fine gravel with some cover, and feed small invertebrate foods and prepared foods. FishBase notes it is shown in public aquariums.
Conservation
FishBase lists the species as Least Concern on the IUCN Red List, assessed 16 July 2024.