Classification / Names
Common names | Synonyms | Catalog of Fishes(genus, species) | ITIS | CoL | WoRMS | Cloffa
Petromyzonti (lampreys) > Petromyzontiformes
(Lampreys) > Petromyzontidae
(Northern lampreys) > Lampetrinae
Etymology: Entosphenus: entos (Gr.), within; sphenos (Gr.), wedge, referring to wedge-shaped tooth within mouth on tongue of E. tridentatus. (See ETYFish); folletti: In honor of Wilbur (“Bill”) I. Follett (1901-1992), Curator of Fishes, California Academy of Sciences, “friend, a collaborator in the studies of holarctic lampreys, and a distinguished scholar of the fishes of California” [authors incorrectly gave Follett’s name as “William”]. (See ETYFish).
Environment: milieu / climate zone / depth range / distribution range
Freshwater; demersal; non-migratory. Subtropical
North America: known only from the types collected from Willow Creek, upper Klamath river system, California.
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 30.0 cm TL male/unsexed; (Ref. 12280)
Morphology | Morphometrics
spines: 0. Adults: 17.6-22.8 cm TL; body proportions, as percentage of TL (based on 6 specimens measuring 18.6-22.8 cm TL): 12.3-14.5 prebranchial length, 9.2-10.6 branchial length, 42.7-48.6 trunk length, 28.4-32.7 tail length, 1.7-2.3 eye length and 6.6-7.8 disc length; 5.7 urogenital papilla length (percentage of branchial length in one spawning male measuring 21 cm TL); trunk myomeres, 61-65. Adult dentition: supraoral lamina, 3 unicuspid teeth, the median one smaller than the lateral ones; infraoral lamina, 5 unicuspid teeth; 4 endolaterals on each side; endolateral formula, typically 2-3-3-2, the fourth endolateral can also be unicuspid; 1-2 rows of anterials; first row of anterials, 2 unicuspid teeth; exolaterals absent; 1 row of posterials with 13-18 teeth, of which 0-4 are bicuspid and the rest unicuspid (some of these teeth may be embedded in the oral mucosa); transverse lingual lamina, 14-20 unicuspid teeth, the median one slightly enlarged; longitudinal lingual laminae teeth are too poorly developed to be counted. Velar tentacles in adults, 8-9, with tubercles; median tentacle is about the same size as the lateral ones immediately next to it; body coloration (preserved), dark brown on dorsal, lateral, and ventral aspects; lateral line neuromasts darkly pigmented; second dorsal fin pigmentation, +++; caudal fin pigmentation, +++; caudal fin shape, spade-like; oral papillae, 13.
Freshwater; in creeks and rivers (Ref. 89241). Non-parasitic lamprey; adults do not feed but remain in the streams where they soon spawn and die. Ammocoetes larvae live as filter feeders in the bottom mud for at least 4 years before metamorphosis.
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
McGinnis, S.M., 1984. Freshwater fishes of California. University of California Press, Berkeley. 316 p. (Ref. 12280)
IUCN Red List Status (Ref. 126983)
Threat to humans
Fisheries: of no interest
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningSpawning aggregationFecundityEggsEgg development
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingNutrientsMass conversion
Estimates based on models
Phylogenetic diversity index (Ref. 82804
= 0.5156 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00126 (0.00057 - 0.00280), b=2.99 (2.80 - 3.18), in cm total length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245
Trophic level (Ref. 69278
): 4.2 ±0.7 se; based on size and trophs of closest relatives
Resilience (Ref. 120179
): Low, minimum population doubling time 4.5 - 14 years (assuming tm=5).
Fishing Vulnerability (Ref. 59153
): Low vulnerability (20 of 100).