A New Species of <i>Pinus</i> Subgenus <i>Pinus</i> Subsection <i>Contortae</i> from Pliocene Sediments of Ch'ijee's Bluff, Yukon Territory, Canada
Bibliographic record
Abstract
Three structurally preserved conifer ovulate cones are described from Pliocene sediments at Ch'ijee's Bluff on the Porcupine River, near Old Crow, Yukon Territory, Canada. Cones are ovoid to conical, symmetrical, 3.4–4.4 cm long and 2.8–3.4 cm wide, with helically arranged cone‐scale complexes. Ovuliferous scales are thin at the base, expanded at the apex, 2 cm long and 1 cm wide, with flat, rhomboidal apophyses and minute dorsal umbos. Pith is parenchymatous with scattered sclerenchyma at its outer edge. The parenchymatous inner cortex contains 12–15 small resin canals. Outer cortex is also parenchymatous with a thin outer sclerenchymatous zone. Vascular tissues of the scale and bract originate as a complete cylindrical trace from the axis stele. Resin canals are abaxial to the scale trace as it separates from the bract. The abaxially concave ovuliferous scale trace splits into separate vascular bundles that alternate with resin canals in the most distal sections. Bracts separate from scales medially, lack abaxial lobes, and contain terete traces that are accompanied by two resin canals. The paired seeds are elliptical, 2.7–3.9 mm long and 2.1–2.5 mm wide, with wings up to 16 mm long. Fossils were compared anatomically with extant species of Pinus section Pinus. The fossil cones most closely resemble those of Pinus contorta Dougl. ex Loud. but differ from any previously described fossils of this species or extant subspecies by a combination of cone characters. The symmetrical cone shape, nonreflexed cone base, flattened apophyses, cone serotiny, and seed wing length distinguish these cones from P. contorta. These cones are described in a new species of Pinus subgenus Pinus Subsection Contortae, Pinus matthewsii sp. nov. Like P. contorta, P. matthewsii may have been a colonizer of open habitats. The scarcity of these fossil cones, the presence of numerous cones of Picea Dietr. and a Pinus monticola–like species and abundant Picea, Pinus, and Betula pollen indicate dense forest cover dominated by spruce, soft pines, and birch.
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 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 | 0.002 |
| Science and technology studies | 0.003 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.003 | 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".