A re-evaluation of species limits in Canadian Arctic Island <i>Puccinellia</i> (Poaceae): resolving key characters
Bibliographic record
Abstract
This study examined morphological variation for species of Puccinellia that have traditionally posed problems of identification in the Canadian Arctic Archipelago. The first part of the study involved a re-examination of several characters that were difficult to define or describe. Microscopic examination of lemma and glume apices revealed that the characters "erose-ciliolate" lemma and glume apex margins are more accurately divided into two characters: degree to which they are erose, and presence of trichomes. These trichomes consist of acute or acuminate cells that protrude 1535 µm from the margin, sometimes with a spinulose tip up to 10 µm long. The term "thickened pedicel" is clarified to mean thickened below the apex in relation to the apex. The second part of the study involved preliminary morphometric analyses on the above-mentioned revised characters, plus other characters previously shown to have low plasticity in this genus, for 10 recognized species that are difficult to distinguish. Many species or species complexes resolved to a small degree, but no taxa formed distinct groups. Correlations among many characters were low, accounting for a low percentage of variation explained by the first few principal components. Hypotheses of species boundaries and a preliminary revised key to species and species groups, incorporating findings from this study, are presented.Key words: Puccinellia, Canadian Arctic, morphology, trichomes, principal components analysis, cluster analysis.
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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 | 0.002 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.004 | 0.003 |
| Science and technology studies | 0.004 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
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".