Gyrodactylidae (Monogenea: Platyhelminthes) gill parasites of Tetragonopterinae (Characiformes: Characidae) from the upper Paraná River floodplain, Brazil
Bibliographic record
Abstract
Abstract Aim: This study records Gyrodactylus neotropicalis and Anacanthocotyle anacanthocotyle in new hosts: Astyanax lacustris and Moenkhausia forestii, on the upper Paraná river floodplain. Besides, ecological aspects of the parasites distribution are explored. Methods Both host species were collected between March and September 2014; monogeneans were removed from the gills using a stereo-microscope and mounted in Hoyer or stained with Gomori’s trichrome and mounted in Balsam of Canada. Illustrations were prepared on a phase contrast microscope. Monogeneans were identified using the appropriate literature. Prevalance, abundance, mean intensity and intensity range were calculated to parasite species in each host. Results Gyrodactylus neotropicalis and Anacanthocotyle anacanthocotyle are recorded in new geographic area, upper Paraná River floodplain, in new host species, A. lacustris and M. forestii and in new infection site, gills. A. anacanthocotyle occur in higher prevalence, abundance and intensity parasitizing A. lacustris, while G. neotropicalis presented higher prevalence, abundance and intensity in M. forestii. Discussion Gyrodactylus neotropicalis described by Kritsky & Fritts, 1970, parasite of Astyanax fasciatus (Cuvier), presented a different shield position between anchors than the specimens studied here; A. anacanthocotyle also described by Kritsky & Fritts, 1970 presented spicules in the cephalic region, what was not observed in the specimens studied here. Plasticity in parasitism may explain the difference between monogenean in different hosts. Conclusion Until now, there was no record of this Gyrodactylidae species parasitizing Characidae fish in South America. Those parasites are the first Gyrodactylidae monogeneans described from A. lacustris and M. forestii.
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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 | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| 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".