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💧 Freshwater 🌡️ Temperate

Pacific brook lamprey

Occidentis pacifica Vladykov, 1973
Max Length
17.5 cm
Max Weight
-
Lifespan
-
Trophic Level
3.8
Depth
-
Climate
Temperate
Resilience
Low
Vulnerability
37.00/100
Typical Length
12.5 cm
Depth Zone
demersal

📖 Overview

Freshwater; creeks and rivers. Metamorphosis occurs in October in Oregon and California. Adults nonparasitic. Based on the dates of collection of spawning individuals in the original description, the spawning period probably occurs between mid-April and August in Oregon, while in California spawning probably occurs between the end of April and the beginning of May .

Scientific Name
Occidentis pacifica
Authority
Vladykov, 1973
Habitat
Freshwater
Climate
Temperate
Max Length
17.5 cm
Trophic Level
3.8
Resilience
Low
Vulnerability
37.00/100
Migration
Non-migratory
Salinity
0–0.5 ppt

🔬 Taxonomy

Genus
Occidentis
Occidentis
Species
Pacific brook lamprey
Occidentis pacifica

🐟 Physical Description

Adults: 9.8-17.5 cm TL. Body proportions, as percentage of TL (based on 39 specimens measuring 9.8-17.3 cm TL): prebranchial length, 8.9-12.8; branchial length, 8.9-11.3; trunk length, 44.7-53.5; tail length, 24.3-35.0; eye length, 1.4-3.0; disc length, 4.1-7.2. Urogenital papilla length, as a percentage of branchial length, in ten spawning males measuring 11.2-13.3 cm TL, 17.8-36.4. Trunk myomeres, 53-58. Dentition: supraoral lamina, 2 unicuspid teeth; infraoral lamina, 6-9 unicuspid teeth, usually 8; usually 3 endolaterals on each side, occasionally 2 on one side; endolateral formulae highly variable with the first two teeth 1-3 and the third 1-2; 1-2 rows of anterials; first row of anterials, 6 unicuspid teeth (in spawning specimens, the teeth in the anterior field may be lost); exolaterals absent; posterials absent; transverse lingual lamina, undetermined number of minute unicuspid teeth on either side of an enlarged median one; longitudinal lingual laminae cusps too small to count. Velar tentacles, 3-6, with tubercles. Body coloration (preserved), dark gray on dorsal and lateral aspects, whitish on ventral aspect. Lateral line neuromasts unpigmented. Extent of caudal fin pigmentation, 1% to

🌀 Behaviour

Behavioural data for Pacific brook lamprey is currently being reviewed.

🦐 Diet

Diet information for Pacific brook lamprey is currently being compiled.

🥚 Reproduction

Reproduction data for Pacific brook lamprey is currently being compiled.

🌍 Habitat & Distribution

Freshwater; demersal; non-migratory. Temperate

🌿 Ecology

Zone Preferences
💧 Freshwater ⬇️ Benthic
Migration
Non-migratory
Trophic Level
3.8±0.8

📐 Morphometrics

Length–Weight Relationship: W = 0.00129 × L2.98 (TL)
Max TL
17.5cm

🌡️ Water Parameters & Tolerance

Salinity Range
0–0.5ppt

📊 Population Risk & Fisheries

Population Resilience
Low
Minimum doubling time
Fishing Vulnerability
37.00/100
Moderate vulnerability
Trophic Level
3.8
Predator
Climate Zone
Temperate
Described By
Vladykov, 1973

👥 Community & Contribute

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