Metacyphocaris helgae Tattersall 1906
Bibliographic record
Abstract
Metacyphocaris helgae Tattersall, 1906 (Figs 3, 4) Metacyphocaris Helgae Tattersall, 1906: 29, pl. 3 fig. 1, pl. 4. — Stephensen, 1912a: 88. — Stephensen, 1912b: 613. — Stephensen, 1913: 113. — Stephensen, 1915: 38. — Stephensen, 1923: 54. — Schellenberg, 1926b: 216, figs 26c, 27. — Schellenberg, 1927: 666, fig. 60. — Pirlot, 1929: 8. — Schellenberg, 1929: 196. — K.H. Barnard, 1932: 37, fig. 5. — Stephensen, 1932: 354. — Stephensen, 1933: 9. — Chevreux, 1935: 28. — Thorsteinson, 1941: 60, pl. 3 figs 31-38. — Shoemaker, 1945: 189. — J.L. Barnard, 1958: 95. — Birstein & Vinogradov, 1958: 222. — Birstein & Vinogradov, 1960: 171. — Gurjanova, 1962: 79, fig. 14. — Hurley, 1963: 22, fig. 3. — Birstein & Vinogradov, 1964: 156. — O'Riordan, 1969: 32. — Thurston & Allen, 1969: 361. — Vader, 1983: 140 (table 1). — Umezu, 1984: 128. — Austin, 1985: 601. — Costello et al., 1989: 32. — Barnard & Karaman, 1991: 502. — Palerud & Vader, 1991: 38. — Lopes et al., 1993: 209. — Thurston, 2001: 684 (table 2). Type localities (for syntypes). 40 miles north by west of Eagle Island, County Mayo, Ireland, eastern North Atlantic Ocean, [approx. 54°30'N 11°30'W], 1152 m over 1189+ m; same locality, 1371 m over 1829+ m; west of Porcupine Bank, eastern North Atlantic Ocean, 53°07'N 15°06'W, 1371 m over 1573 m; 50 miles north by west of Eagle Island, County Mayo, Ireland, eastern North Atlantic Ocean, [approx. 54°30'N 11°30'W], 1097 m over 2195 m; same locality, 2113 m over 2195 m. Material examined. 1 specimen, immature, 11.5 mm, MV J15797, south of Point Hicks, Victoria, Australia, 38°27.20'S 149°09.70'E, 8 m rectangular midwater trawl, 22 July 1986, M.F. Gomon et al., RV Franklin, stn SLOPE 24. Distribution. Atlantic, Indian and Pacific Oceans, between 65°N and 40°S; to 4740 m depth (see remarks). Remarks. Tattersall (1906: 30), in his original description of Metacyphocaris helgae, said it had no mandibular palp, only a "very small rounded tubercular appendage". We have examined a specimen from the syntype series and confirm this description. Tattersall used this character to separate Metacyphocaris from Paracyphocaris. K.H. Barnard (1932) reported material of M. helgae from the South Atlantic Ocean with a rudimentary 2-articulate mandibular palp. Shoemaker (1945) also reported material with a rudimentary 2-articulate mandibular palp from Bermuda in the western North Atlantic Ocean and Hurley (1963) reported material with a 1- articulate palp from the San Nicholas Basin, eastern Pacific Ocean. There are now 18 literature reports of M. helgae material, recording more than 100 specimens. Most are not illustrated or described so it is not possible to assess the variation in the mandibular palp or any other characters which might indicate separate species. The single specimen we record here has no mandibular palp and matches very well with Tattersall's type material. The depth range cited above is very unlikely. According to Thurston (2010 in litt.) this is ‘the bottom depth under the 0–4990 m haul listed in Birstein & Vinogradov (1960). Virtually all Birstein & Vinogradov hauls were made with open nets and the depths quoted are metres of wire out. The same is true for most mid-water hauls, even those made in horizontal mode. I have unpublished data for M. helgae collected in the North Atlantic at 60N20W, 53N20W, 40N20W and 30N23W to depths of 2000 m or more. Based on an analysis of more than 200 specimens obtained using the opening/closing IOS RMT1+8 nets, the species occurs in all layers from 600–700 m down to 1250–1500 m. Single specimens were caught at 500–600 m and 1500–2000 m.’
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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) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.002 | 0.001 |
| Science and technology studies | 0.002 | 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) | 0.035 | 0.011 |
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".