Alaskan brook lamprey
Adult preserved specimens gray-brown dorsally, white ventrally, with a dark blotch on 2nd dorsal fin; tail dark. Teeth on disk blunt and weakly cornified. Supraoral bar with 2 cusps. Infraoral bar with 6-11 cusps. Lateral tooth plates 3, central pair with 2 cusps. Tongue teeth poorly developed and blunt. Posterial teeth present. A few, supplementary marginal teeth present on the lateral areas of the disk. Typical length 12-17 cm TL (Ref. 43939). Trunk myomeres 66-72 (Ref. 43938).