Validity of Lampetra pacifica (Petromyzontiformes: Petromyzontidae), a brook lamprey described from the lower Columbia River Basin
Bibliographic record
Abstract
The Pacific Brook Lamprey, Lampetra pacifica Vladykov, 1973 was described from the lower Columbia River Basin near Portland, Oregon. Subsequently, L. pacifica has generally been treated as a junior synonym of the Western Brook Lamprey, L. richardsoni Vladykov and Follett, 1965, a species described from the Fraser River Drainage east of Vancouver, British Columbia. We reexamine the available morphological data used by previous authors (trunk myomere counts), report on recent collections from the Columbia Basin, and reinterpret the trunk myomere data in the context of recent genetic sampling from the same populations. Populations of L. pacifica are distinguished from those of L. richardsoni by trunk myomere counts of 53–60 (means 59), respectively, and by genetic sequence divergence (cyt b) of 2.85 to 3.20%. We find no support for placing L. pacifica in the synonymy of L. richardsoni and recognize L. pacifica as a valid species. However, we recognize that there is considerable unresolved diversity in the western North American lampreys and recommend restriction of L. pacifica to the Columbia Basin, suggesting that unresolved populations of Lampetra brook (non-parasitic) lampreys outside the basin with mean trunk myomere counts below 59 be referred to as L. cf. pacifica, until further systematic information is available.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.007 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.002 | 0.001 |
| Science and technology studies | 0.003 | 0.002 |
| Scholarly communication | 0.002 | 0.001 |
| Open science | 0.001 | 0.002 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.002 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".