Fossil species in Boehmerieae (Urticaceae) in Dominican and Mexican amber: a new genus (<i>Ekrixanthera</i>) and two new species with anemophilous pollination by explosive pollen release, and possible lepidopteran herbivory
Bibliographic record
Abstract
The first fossil flowers of Neotropical Urticaceae (Boehmerieae) are described from the Dominican Republic and Mexico as belonging to a new genus, Ekrixanthera. Ekrixanthera hispaniolae sp. nov. from Dominican amber has pentamerous staminate flowers on short pedicels with a pilose pistillode and heteromorphic pilose tepals: two are clavate and three linear. Ekrixanthera ehecatli sp. nov. has pentamerous staminate flowers lacking pedicels, a pistillode with greatly reduced pilosity, glabrous and heteromorphic tepals with two linear and three wedge-shaped with truncate tips. The presence or absence of a pedicel, heterotrophic condition of the tepals, and the presence or absence of pilosity of the pistillode and tepals separate the two species. Those characters, together with the pentamerous flowers separate both fossil species from extant genera. The floral structures indicate explosive pollen release and pollination by wind (anemophily). Pistillate flowers have not been found for this usually dioecious tribe. Lepidopteran herbivory is suggested by a damaged stipule in one specimen and a nymphalid butterfly (Vanessa-like) caterpillar that may have used Ekrixanthera as a food plant is illustrated. The fossils establish an early lineage of Boehmerieae with characteristic explosive pollen release and perhaps associated herbivorous insects in the West Indies and North America during the mid-Tertiary.
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 | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 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) | 0.002 | 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".