Diets of two congeneric species of crayfish worm (Annelida: Clitellata: Branchiobdellidae) from western Canada
Bibliographic record
Abstract
Crayfish worms (Branchiobdellidae) are obligatory ectosymbionts of crustaceans, primarily crayfish. Little is known about their diets or ecology. A single crayfish can host several species and age classes of branchiobdellidans at one time, creating the potential for intra- and inter-specific competition. Coexistence of competitors can be promoted through dietary differences; therefore, we examined gut contents of Cambarincola chirocephalus Ellis, 1919 and Cambarincola vitreus Ellis, 1919, two species of branchiobdellidan occasionally found on the same host (the crayfish Orconectes virilis (Hagen, 1870) in Western Canada) to assess evidence of dietary niche partitioning. We also compared gut contents of conspecific adults and juveniles to determine whether diets differed with age. We found a range of diatoms and invertebrates, particularly rotifers, in the guts of both Cambarincola species. The species appear to have different diets, in that guts of C. chirocephalus contained more invertebrate material than did those of C. vitreus. There was no statistical difference in composition of gut contents between adult and juvenile conspecifics. We found very limited evidence of dietary niche expansion in C. vitreus in the absence of C. chirocephalus. The observed dietary differences between species may promote their continued coexistence in areas where their ranges overlap.
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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 | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.002 | 0.001 |
| Science and technology studies | 0.002 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 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".