Granulina crystallina Smriglio, Gubbioli & Mariottini, 2000 Figs 1, 2E Granulina crystallina Smriglio, Gubbioli & Mariottini, 2000: 55, 58, figs 3, 13–16; type locality off Mauritania (80–90 m). Smriglio et al. (2000) reported 22 specimens, of which some empty shells from off Mauritania (80–90 m) without further details. The holotype was deposited in the Bologna Zoology Museum (MZB14031). Twenty-one paratypes were retained in private collections. Material examined (48 shells) MAURITANIA – off Banc d’Arguin • 11 shells; 20.3667° N, 17.6667° W; depth 200 m; 28 Oct. 1978; CANCAP stn 3.120; sandy clay with shells; van Veen grab; SaM • 3 shells; 18.9833° N, 16.8333° W; depth 203 m; 30 Oct. 1978; CANCAP stn 3.140; sandy clay with shells; van Veen grab; RMNH.MOL.351807 • 7 shells; Arguin mud wedge; 20.4569° N, 17.6795° W; depth 142 m; 24 Oct. 2010; MSM16 –3 stn GeoB14706; box core in muddy silt; SaM; box core in muddy silt; SaM • 1 shell; 19.94° N, 17.48° W; depth 151 m; 22 May 1988; Tyro Mauritania I stn B5; RMNH.MOL.351808. – off Nouakchott • 1 shell; off Nouakchott; 17.0967° N, 16.73° W; depth 127 m; 17 Feb. 1977; M44 stn 193–KG626; box core; SMF • 3 shells; 17.045° N, 16.7783° W; depth 199 m; 11 Feb. 1977; M44 stn 133–KG616; box core; SMF. WESTERN SAHARA – off Cap Blanc • 22 shells; 21.325° N, 17.37° W; depth 81 m; 25 Feb. 1977; M44 stn 235–KG649; box core; SMF. Remarks Smriglio et al. (2000) indicated a holotype height of 2.4 mm; our set indicates a maximum height of 3.1 mm. The species is a largest member of the four coffin-shaped species from Mauritania. It has weak labial denticles, a clear angular outline and it shows a weak (ab-)apical rostration. The species is known from empty shells in the latitudinal range 17.0– 21.4° N. It is commonly found on the lower shelf at depths of 52–210 m in silty sand.

Published as part of Elm, Laura-Marie Von & Hoffman, Leon, 2024, Revision of deep-water species in Granulina (Gastropoda: Granulinidae) from Mauritania and Western Sahara, pp. 268-291 in European Journal of Taxonomy 925 on page 276, DOI: 10.5852/ejt.2024.925.2467, http://zenodo.org/record/10837829