Endolymphatic structures in headshields of the osteostracan genus Tremataspis (Agnatha) from the Silurian of Estonia
Bibliographic record
Abstract
Details of the endolymphatic structures are described for the first time in the headshields of the osteostracan genus Tremataspis from the Silurian of Estonia. Tiny platelets, here termed covering platelets, are located within the openings of the endolymphatic duct. The details of their shapes and arrangements differ among the four studied species. In Tremataspis schmidti Rohon and Tremataspis milleri Patten, the covering platelets are usually arranged in an oval or circular shape around the opening of the endolymphatic duct. These species can have smooth, flat covering platelets at the mouth of an irregularly funnel-shaped aperture in the dorsal shield; the funnel often has a posterior extension. In Tremataspis rohoni Robertson and Tremataspis mammillata Patten, a distinct circular arrangement of platelets does not occur; instead, their funnel was capped with a few (2–3) smooth, flat covering platelets. The funnel of T. milleri sometimes has a long postero-lateral extension, while that of T. mammillata can have a short extension; no extensions of the funnel have been observed in T. schmidti or T. rohoni. The diameter of the pores in the covering platelets is larger than that of the pores in the superficial layer of the headshield and much larger than the diameter of the pores in the porous fields (these are thin perforated bony septa subdividing the sensory canals horizontally into lower and upper parts). In T. milleri, the larger pores are located on the side of the covering platelets that is closer to the body midline. The discovered system of covering platelets possibly functioned as a sieve for allowing in suitable grains of material and preventing material that is too fine or too coarse, or not sufficiently dense, from entering the inner ear.
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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 | 0.001 | 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) | 0.002 | 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".