New information on the cranial and postcranial anatomy of the early synapsid <i>Ianthodon schultzei</i> (Sphenacomorpha: Sphenacodontia), and its evolutionary significance
Bibliographic record
Abstract
Abstract. Newly identified material belonging to the holotype specimen of Ianthodon schultzei substantially increases our knowledge of this poorly known basal sphenacodont synapsid from the fossil site in Garnett, Kansas (Missourian, Late Pennsylvanian). The original description, based on a partial dermal skull roof, is augmented with information on the palate and braincase, together with data on the mandible and a few postcranial elements. The known skeletal morphology resembles that of Haptodus garnettensis, another synapsid taxon known from this locality, but with fewer marginal, distinctly recurved teeth and smaller teeth on the transverse flange of the pterygoid. Although recognizing that the holotype and only known specimen represents a juvenile individual, Ianthodon appears to reflect a more basal sphenacodontian condition than H. garnettensis. A restricted phylogenetic analysis based on previous work and newly scored characters for Ianthodon, Cutleria and Pantelosaurus supports this hypothesis. The Garnett locality appears to preserve an assemblage of synapsids (Haptodus, Ianthasaurus, Ianthodon) that are close to the base of the large clade that includes Edaphosauridae and Sphenacodontia, suggesting that an initial diversification of this clade occurred well within the Carboniferous Period.
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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 | 0.001 |
| 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) | 0.004 | 0.001 |
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".