Taxonomy, biogeography and DNA barcodes of<i>Geodia</i>species (Porifera, Demospongiae, Tetractinellida) in the Atlantic boreo-arctic region
Bibliographic record
Abstract
Geodia species north of 60°N in the Atlantic appeared in the literature for the first time when Bowerbank described Geodia barretti and G. macandrewii in 1858 from western Norway.Since then, a number of species have been based on material from various parts of the region: G. simplex, Isops phlegraei, I. pallida, I. sphaeroides, Synops pyriformis, G. parva, G. normani, G. atlantica, Sidonops mesotriaena (now called G. hentscheli), and G. simplicissima.In addition to these 12 nominal species, four species described from elsewhere are claimed to have been identified in material from the northeast Atlantic, namely G. nodastrella and G. cydonium (and its synonyms Cydonium muelleri and Geodia gigas).In this paper, we revise the boreo-arctic Geodia species using morphological, molecular, and biogeographical data.We notably compare northwest and northeast Atlantic specimens.Biological data (reproduction, biochemistry, microbiology, epibionts) for each species are also reviewed.Our results show that there are six valid species of boreo-arctic Atlantic Geodia while other names are synonyms or mis-identifications.Geodia barretti, G. atlantica, G. macandrewii, and G. hentscheli are well established and widely distributed.The same goes for Geodia phlegraei, but this species shows a striking geographical and bathymetric variation, which led us to recognize two species, G. phlegraei and G. parva (here resurrected).Some Geodia are arctic species (G.hentscheli, G. parva), while others are typically boreal (G.atlantica, G. barretti, G. phlegraei, G. macandrewii).No morphological differences were found between specimens from the northeast and northwest Atlantic, except for G. parva.The Folmer cytochrome oxidase subunit I (COI) fragment is unique for every species and invariable over their whole distribution range, except for G. barretti which had two haplotypes.18S is unique for four species but cannot discriminate G. phlegraei and G. parva.Two keys to the boreo-arctic Geodia are included, one based on external morphology, the other based on spicule morphology.
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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 | 0.002 | 0.001 |
| 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 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".