Speirazafra Monsecour & Raines, 2024, gen. nov.

Speirazafra gen. nov. Type species: Speirazafra wakensis sp. nov.; OD, herein. Diagnosis. Shell moderate size (up to 4 mm), biconical, elongate, not shouldered. Protoconch paucispiral. Teleoconch of about 3 whorls; suture slightly impressed. Spiral sculpture of pronounced cords and rather deep interspaces; basal cords clearly present on last whorl. Outer lip thickened and smooth apart from continuation of basal cords. Inner lip slightly thickened with strong denticles inside and posterior sinus. Columella without callus, weak parietal callus. Canal short, open. Remarks. The genus Speirazafra is proposed for a unique little shell which cannot be placed in any of the known columbellid genera. Speirazafra shows some superficial resemblances with a few members of the genus Macrozafra Finlay, 1926. The spiral sculpture and lack of clear columellar callus are similar to those of Macrozafra mariae Powell, 1940. However, the new genus differs from other members of Macrozafra by its non-shouldered whorls and unique aperture morphology, which is much narrower with clearly pronounced adapical sinus. Moreover, the genus Macrozafra is only found in temperate waters around New Zealand and not reported in the more tropical waters. The genus Zafra A. Adams, 1860 has a similar general biconical outline and aperture proportion. However, Speirazafra has a completely different sculpture of spiral cords and grooves, while Zafra has an axial sculpture of strong ribs. The columella of Speirazafra is also not callused, while Zafra has a clear callus. Members of Retizafra are about the same size and general outline, but Speirazafra has sculpture of only strong spiral cords. Speirazafra differs from Mitropsis by having wider outline, less shouldered whorls, weaker incised suture, less S-shaped aperture and shorter siphonal canal. Speirazafra differs from Decipifus Olsson & McGinty, 1958, a genus with species in Caribbean, Panamic and South African provinces, by not having axial sculpture, and narrower aperture with stronger denticulation. Speirazafra can be easily separated from other genera with members of about the same size in the Indo-Pacific region like Ascalista, Euspiralta, Mitrella and Mokumea by its spiral sculpture which is lacking on those genera and different apertural shape. Etymology. Greek speira meaning spiral and Zafra a genus of small columbellid species. After the spiral cords on the shell and the small size comparable to Zafra.