New genera for species of Jassa Leach (Crustacea: Amphipoda) and their relationship to a revised Ischyrocerini
Bibliographic record
Abstract
Four Southern Hemisphere and one Northern Hemisphere species of Jassa (Crustacea: Amphipoda: Ischyrocerini) are removed from this genus. The south temperate Jassa barnardi Stephensen, 1949 is synonymized with Ventojassa frequens (Chilton, 1883). The south temperate and subantarctic Jassa multidentata Schellenberg, 1931 and Jassa wandeli Chevreux, 1906 are transferred to Pleojassa n. gen., with the addition of P. lowryi n. sp., P. moorei n. sp. and P. orientalis n. sp. Hemijassa Walker, 1907 is resurrected for the Antarctic Jassa goniamera Walker, 1903. The Northern Hemisphere Jassa ocia (Bate, 1862) is transferred to Plumulojassa n. gen. and shown to range throughout the temperate coasts of the northeastern Atlantic and its eastern seas. Placed in context of the other genera of the Ischyrocerini Stebbing, 1899, Jassa, Pleojassa, Hemijassa and Plumulojassa join Parajassa Stebbing, 1899 in having a unique uropod 3 morphology. Characteristics of the uropod 3 and other appendages are used to revise four other genera of the Ischyrocerini. Ischyrocerus Krøyer, 1838 now becomes a temperate to polar genus, with Neoischyrocerus Conlan, 1995 embracing tropical species of Ischyrocerus and all members of Coxischyrocerus Just, 2009 and Tropischyrocerus Just, 2009. A new diagnosis and illustrated key to the 18 genera of Ischyrocerini is given.
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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 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.001 |
| Bibliometrics | 0.002 | 0.001 |
| Science and technology studies | 0.002 | 0.002 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.006 | 0.002 |
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".