HomeFish encyclopediaRay-finned fishesPerch-like fishRonquilsSmallmouth ronquil Smallmouth ronquil (Bathymaster leurolepis) Scientific name: Bathymaster leurolepis McPhail, 1965 The Smallmouth ronquil (Bathymaster leurolepis) is a marine fish of the family Bathymasteridae. Native range: North Pacific, Japan to the Gulf of Alaska. BiologyDorsal spines (total): 2; Dorsal soft rays (total): 41-45; Anal spines: 1 - 2; Anal soft rays: 29 - 34. Pelvic fin thoracic, consisting of 1 spine and 5 soft rays, not covered with scales. Length of scaled portion of caudal fin less than 1/2 its whole length. Maxillary extending to below about middle of eye. Attains about 20 cm SL.Source: FishBase, licensed CC BY-NC 4.0. Species factsScientific nameBathymaster leurolepisFamilyBathymasteridae (Ronquils)OrderPerciformes (Perch-like fish)ClassActinopterygii (Ray-finned fishes)Maximum length21.0Depth range0–80 m (0–262 ft)EnvironmentMarine; demersal; depth range 0 - 80 mClimateTemperateDistributionNorth Pacific: Japan to the Gulf of Alaska.Conservation status (IUCN)Not EvaluatedThreat to humansHarmless SourcesTaxonomy, distribution and biology data: FishBase (Froese, R. and D. Pauly, eds.), licensed CC BY-NC 4.0.Last updated 27 September 2026