Bajocian (middle Jurassic) Ammonitina of New Zealand
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
Abstract A relatively rich, previously unknown fauna of Ammonitina is described from the Bajocian of southwest Auckland. The great majority are Sphaeroceratidae. The Chondroceras fauna has yielded C. orbignyanum and C. (Defonticeras) cf. oblatum, clearly indicating the Humphriesianum Chron. Also associated is the bivalve index Retroceramus inconditus. The superjacent fauna of Waikatoceratinae (n. subfam.) is almost exclusively endemic to New Zealand, with Waikatoceras crassum, W. hudsoni, Opuatia circularis, O. inflata, and O. challinori n. genn. et spp. Accessory taxa include Chondroceras cf. orbignyanum, and Toxamblyites aff. densicostatus, previously known only from the upper Lower Bajocian of Europe and North Africa. However, stratigraphic evidence together with the bivalve index Retroceramus marwicki clearly date the Waikatoceratinae fauna as mostly post‐Humphriesianum Chron (i.e., early Late Bajocian). The presence of Toxamblyites in this fauna suggests that its range was one chron longer in the Southwest Pacific than in Eurafrica—unless the fragmented specimens were reworked, which is considered unlikely. Relatively rare and often immature phylloceratids and lissoceratids are also associated. Other single finds of Middle Jurassic Ammonitina from other New Zealand regions are also discussed. Other stratigraphically important taxa include the bivalve Meleagrinella n. sp. and the belemnite Hibolithes catlinensis. The boundary between the Middle and Upper Temaikan regional substages can be defined by the first occurrence of either Retroceramus marwicki or of Waikatoceratinae; both boundaries lie in the Humphriesianum Chron. The bivalve index is widespread, permitting inter‐regional correlation, whereas the ammonite index allows reasonably precise dating.
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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 | 0.000 | 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 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 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 it