A late Furongian trilobite assemblage from the eastern Cordillera Oriental (Santa Rosita Formation; Jujuy, Argentina) and its biostratigraphic significance
Bibliographic record
Abstract
The trilobite Parabolina frequens argentina Zone is widely represented in the upper Furongian of northwestern Argentina. A fossil assemblage from the lower Santa Rosita Formation at Quebrada de Abra Blanca, Jujuy Province, is described herein. Parabolina frequens argentina (Kayser) and Parabolinella coelatifrons Harrington & Leanza have previously been reported from other localities of the biozone, whereas Lotagnostus hedini (Troedsson) is here described from South America for the first time. The latter provides high resolution data on the age of the P . frequens argentina Zone in the eastern Cordillera Oriental, where conodont-bearing strata have not been found yet. L . hedini exhibits a short biostratigraphic range, restricted to the latest Furongian of China (Xinjiang, Bulbolenus Zone; western Zhejiang, Lotagnostus hedini Zone), Kazakhstan ( Euloma limitaris - Taoyuania Zone) and ?Canada (western Newfoundland, Phylacterus saylesi Fauna). In China and Kazakhstan, it occurs in association with, or a few meters below, the first appearance of the conodont Cordylodus proavus ; a fact that increases the potential for global correlation.
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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 | 0.000 |
| Scholarly communication | 0.001 | 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".