Klamath Lamprey

Adults: 13.6-26.9 cm TL. Adult body proportions, as percentage of TL (based on 29 specimens measuring 13.6-26.9 cm TL): prebranchial length, 13.0-16.4; branchial length, 8.2-11.8; trunk length, 42.5-52.0; tail length, 27.0-34.9; eye length, 1.4-2.7; disc length, 7.8-10.5. The intestinal diameter in feeding individuals is 0.45 cm. Trunk myomeres, 58-65. Dentition: the marginals in the anterior and lateral fields are of two different sizes, small and with an elongated base, while those in the posterior field are small; exceptionally, one or two of these elongate marginals on each side lie in the middle of the lateral fields and therefore qualify as exolaterals; supraoral lamina, 3 unicuspid teeth, the median one smaller than the lateral ones; infraoral lamina, 5-6 unicuspid teeth, predominantly 5; 4 endolaterals on each side, rarely 3 on one side; endolateral formula, typically 2-3-3-2, the second endolateral may also be uni-, bi- or quadricuspid, the third endolateral may also be quadricuspid, and the fourth endolateral may be absent, but if present, also be uni-, bi- or quadricuspid; 2 rows of anterials; first row of anterials, 4-5 unicuspid teeth; exolaterals not present as rows but 1 or 2 on each side may be present; 1 row of posterials with 16-20 teeth, of which 0-15 are bicuspid and the rest unicuspid; transverse lingual lamina, 20-29 unicuspid teeth, the median one slightly enlarged; longitudinal lingual laminae each with 24-33 unicuspid teeth. Velar tentacles, 7-9, with tubercles and wings consisting of a very short tentacle on either side. Median tentacle shorter than the lateral ones immediately next to it. Body coloration (preserved), dark brown on dorsal, lateral, and ventral aspects. Lateral line neuromasts darkly pigmented. Caudal fin and second dorsal fin pigmentation, coverage of 75% or more. Caudal fin shape, spade-like. Oral fimbriae, 98-111. Oral papillae, 12-20.

Adults parasitic on fishes. Known to feed on fishes perhaps of commercial importance, but these were not identified (Ref.89241).

Occurs in large rivers, impoundments and lakes. Parasitic (Ref. 5723). Known to feed on fishes perhaps of commercial importance, but these were not identified (Ref. 89241).

fisheries: of no interest