Smooth lumpsucker (Aptocyclus ventricosus)

Scientific name: Aptocyclus ventricosus Pallas, 1769

The Smooth lumpsucker (Aptocyclus ventricosus) is a marine fish of the family Cyclopteridae.

Biology

Dorsal spines (total): 0; Dorsal soft rays (total): 8-9; Anal spines: 0; Anal soft rays: 7 - 9. Brownish gray with dark spots dorsally, muddy gray ventrally. Caudal fin rounded; pectoral fins large and broadly based; pelvic fins modified to form a clinging disc with a thickened margin on the ventral surface of the body. Skin naked without scales and tubercles. First dorsal fin completely embedded under the skin. Disk rudimentary in young, well developed in adults.

Source: FishBase, licensed CC BY-NC 4.0.

Species facts

Scientific name: Aptocyclus ventricosus
Family: Cyclopteridae (Lumpfishes)
Order: Scorpaeniformes (Scorpionfishes and Flatheads)
Class: Actinopterygii (Ray-finned fishes)
Maximum length: 41.0
Depth range: 0–1700 m (0–5577 ft)
Environment: Marine; benthopelagic; depth range 0 - 1700 m
Climate: Temperate
Distribution: North Pacific: Pusan, Korea north (outside the Sea of Okhotsk) to Providence Bay in the Anadyr Gulf of the Bering Sea, throughout the Aleutian Basin and islands, and southeast to Mathieson Channel, British Columbia, Canada.
Conservation status (IUCN): Not Evaluated
Threat to humans: Harmless
Uses: Fisheries:
Resilience: Low, minimum population doubling time 4.5 - 14 years (Preliminary K or Fecundity.)

Sources

Taxonomy, distribution and biology data: FishBase (Froese, R. and D. Pauly, eds.), licensed CC BY-NC 4.0.

Last updated 27 September 2026