Conoidea Fleming, 1822

Gofas, Serge, Luque, Ángel A., Oliver, Joan Daniel, Templado, José & Serrano, Alberto, 2021, The Mollusca of Galicia Bank (NE Atlantic Ocean), European Journal of Taxonomy 785 (1), pp. 1-114 : 64-66

Superfamily Conoidea Fleming, 1822

This species-rich superfamily is represented on Galicia Bank by members of the families Cochlespiridae Powell, 1942 (Aforia Dall, 1889), Borsoniidae Bellardi, 1875 (Drilliola Locard, 1897, Retidrillia J.H. McLean, 2000), Mangeliidae P.Fischer, 1883 (Kurtziella Dall, 1918),and mostly Raphitomidae Bellardi, 1875 ( Pleurotomella Verrill, 1872 , Gymnobela Verrill, 1884, Austrobela Criscione, Hallan, Puillandre & Fedosov, 2020, Teretia Norman, 1888, Neopleurotomoides Shuto, 1971). The separation of Pleurotomella species is very difficult, Bouchet & Warén (1980) should be consulted for identification in this genus.

Key to the species of Conoidea found in the GB

1. Sculpture formed by clearly predominant spiral cords or keels ....................................................... 2

– Sculpture of axial ribs and spiral cords ............................................................................................. 6

2. Shell up to 35 mm high, with two keels and finer spiral threads ........................................................ ........................................................... Aforia serranoi Gofas, Kantor & Luque, 2014 ( Fig. 26A–C )

– Shell usually less than 10 mm, not keeled or with only one subsutural keel ................................... 3

3. Last whorl hardly more than half of total height, protoconch ribbed ................................................. ........................................................................... Drilliola loprestiana (Calcara, 1841) ( Fig. 26F–G )

– Last whorl nearly two-thirds of total height, protoconch not ribbed ............................................... 4

4. Subsutural keel present; sometimes a very faint ribbing .................................................................... ......................................... Gymnobela subaraneosa (Dautzenberg & H. Fischer, 1896) ( Fig. 27I–J )

– No subsutural keel ............................................................................................................................ 5

5. Spiral cords coarse, protoconch small <0.5 mm ................... Teretia teres (Reeve, 1844) ( Fig. 26N )

– Spiral cords fine, protoconch large> 0.7 mm ..................................................................................... .......................................... Teretia megalembryon (Dautzenberg & H. Fischer, 1896) ( Fig. 26L–M )

6. Spiral sculpture comprising spiral cords, and finer spiral threads in the interspaces of the main cords ............................................................................... Kurtziella serga (Dall, 1881) ( Fig. 27A–B )

– Spiral cords or threads maybe unequal, but not as above ................................................................. 7

7. Protoconch whitish, with a marked peripheral keel and axial riblets ................................................. ........................... Neopleurotomoides callembryon (Dautzenberg & H. Fischer, 1896) ( Fig. 27E–F )

– Protoconch generally brownish, with a cris-cross microsculpture of oblique riblets ....................... 8

8. Protoconch globose with a blunt apex .............................................................................................. 9

– Protoconch conical with a pointed apex ......................................................................................... 10

9. Whorls with a sharp keel bearing fine knobs ......... Retidrillia pruina (Watson, 1881) ( Fig. 26D–E )

– Whorls bluntly angular, with definite flexuose ribs ............................................................................ ......................................................................... Pleurotomella packardii Verrill, 1872 ( Fig. 27C–D )

10. Shell robust, distinctly shouldered, with fine spiral cordlets and broader axial folds .....................11

– Shell thin, not distinctly shouldered, with spiral cords and axial ribs ............................................ 12

11. Shell stout (diameter more than half the height), ribs few ................................................................. .......................................................................... Gymnobela abyssorum ( Locard, 1897) ( Fig. 26H–I )

– Shell slender (diameter less than half the height), ribs numerous ...................................................... .................................... Austrobela pyrrhogramma (Dautzenberg & H. Fischer, 1896) ( Fig. 26J–K )

12. Shell rather solid, brownish with faint spiral banding ........................................................................ .......................................................... Pleurotomella gibbera Bouchet & Warén, 1980 ( Fig. 27G–H )

– Shell white or vitreous except for brown protoconch ..................................................................... 13

13. Ribs thin and flexuous, much narrower than interspaces; spiral cords delicate and also widely spaced ....................... Pleurotomella coelorhaphe (Dautzenberg & H. Fischer, 1896) ( Fig. 27K–L )

– Ribs rather robust, may be oblique but not definitely flexuous ...................................................... 14

14. Ribs and cords forming a definite lattice, with interspaces about twice as broad as those; ribs ca 12 on last whorl ............ Pleurotomella eurybrocha (Dautzenberg & H. Fischer, 1896) ( Fig. 27M–N )

– Ribs and cords with interspaces only slightly broader than them, ribs ca, 20 on last whorl .............. .......................................... Pleurotomella demosia (Dautzenberg & H. Fischer, 1896) ( Fig. 27O–P )

Figures

Fig. 26. Conoidea 1 (Cochlespiridae, Borsoniidae, Raphitomidae). A–C. Aforia serranoi Gofas, Kantor & Luque, 2014, holotype, BANGAL 0711, V10, 1720 m, 35 mm, and detail of the protoconch. D–E. Retidrillia pruina (Watson, 1881), BANGAL 0711, V5, 1631 m, 11.7 mm. F–G. Drilliola loprestiana (Calcara, 1841), SEAMOUNT 1, DW108, 1110–1125 m, 6.8 mm. H–I. Gymnobela abyssorum (Locard, 1897), SEAMOUNT 1, DW116, 985–1000 m, 10.0 mm. J–K. Austrobela pyrrhogramma (Dautzenberg & H. Fischer, 1896), SEAMOUNT 1, DW116, 10.8 mm. L–M. Teretia megalembryon (Dautzenberg & H. Fischer, 1896), SEAMOUNT 1, DW116, 985–1000 m, 3.3 mm. N. Teretia teres (Reeve, 1844), SEAMOUNT 1, DW106, 765 m, 10.1 mm. Scale bars: A–B = 10 mm; C–N = 1 mm.

Fig. 27. Conoidea 2 (Mangeliidae, Raphitomidae). A–B. Kurtziella serga (Dall, 1881), SEAMOUNT 1, DW115, 880–885 m, 11.3 mm.C–D. Pleurotomella packardiiVerrill, 1872, BANGAL 0711,V2, 1706 m, 8.9 mm. E–F. Neopleurotomoides callembryon (Dautzenberg & H. Fischer, 1896), SEAMOUNT 1, DW111, 675–685 m, 7.1 mm. G–H. Pleurotomella gibbera Bouchet & Warén, 1980, SEAMOUNT 1, DW116, 985–1000 m, 4.2 mm. I–J. Gymnobela subaraneosa (Dautzenberg & H. Fischer, 1896), SEAMOUNT 1, DW116, 4.3 mm. K–L. Pleurotomella coelorhaphe (Dautzenberg & H. Fischer, 1896), SEAMOUNT 1, DW116, 10.0 mm. M–N. Pleurotomella eurybrocha (Dautzenberg & H. Fischer, 1896), SEAMOUNT 1, DW108, 1110–1125 m, 5.5 mm. O–P. Pleurotomella demosia (Dautzenberg & H. Fischer, 1896), SEAMOUNT 1, DW111, 6.5 mm. Scale bars = 1 mm.