Diagnosis. Ventral sucking disk present, small to large. Nostrils single (one on each side of snout). Teeth simple or trilobed. Pseudobranchs absent. Pectoral fins with or without notch forming lower and upper lobes, usually with fewer rays than in anal fin. Pleural ribs present or absent.
Two subgenera, Careproctus sensu stricto and Careproctula Andriashev 2003. Careproctus s.s. is defined by four pectoral radials, some notched with interradial fenestrae, teeth more or less trilobed; well developed pleural ribs, a divided hypural plate usually with 14 (rarely with 11 or 12) rays; and (31) 35–39 pectoral fin rays. Careproctula species have 2–4 unnotched radials without fenestrae, teeth generally simple or shouldered, rarely trilobed; pleural ribs generally absent, fused hypural plate usually with 10 (8–12) rays, and 33 or fewer pectoral fin rays.
Distribution. About 49 species in the Southern Hemisphere, known from Australia, east and west coasts of South America, Falkland and other subantarctic islands, and Antarctica. Three species known from New Zealand waters (Fig. 4).