A NEW CHANNID (TELEOSTEI: CHANNIFORMES) FROM THE EOCENE AND OLIGOCENE OF EGYPT
Bibliographic record
Abstract
Upper Eocene and lower Oligocene deposits of the Jebel Qatrani Formation, Fayum Depression, Egypt, have provided a number of skulls and other bones that belong to a species of snakehead (Channidae). This material is morphologically more similar to species of Parachanna, rather than species of Channa, and is here described as a new species, Parachanna fayumensis. It differs from the other species of the genus in possessing a prominent tooth patch on the posterior end of the parasphenoid.This new species of channid is the oldest member of the family known from Africa. Prior to this record, the oldest African fossil channid material was found in Mio–Pliocene deposits. This lack of information on the African fossil record leads to biogeographic reconstructions in which channids were believed to have arisen in Asia and invaded Africa through fresh waters, only after the two continents were connected in the Miocene. The Egyptian material shows that channids were in the fresh waters of Africa in the latest Eocene. Either a freshwater connection existed between Africa and Asia before or during the late Eocene, or members of the Channidae were able to migrate through marine waters to attain their current distribution.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 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 teacher head, 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".