Mitrella harryleei Monsecour & Raines, 2024, sp. nov.

Mitrella harryleei sp. nov. Figures 2 A–F Type Material. Holotype LACM 2710, 3 Paratypes LACM 2711, 3 Paratypes MNHN-IM-2018-1778, 4 Paratypes CKM, 4 Paratypes MSF fa177. Type Locality. Northern Mariana Islands, Saipan, The Grotto, 15.2702 o N, 145.8346 o E, 30 m deep. Distribution. Currently only known from the type locality. Description. Shell of moderate size for genus, up to 5.7 mm; fusiform, elongate. Protoconch paucispiral, bulbous, of 1.5–1.7 smooth whorls. Transition to teleoconch indistinct. Teleoconch of 4–4.2 whorls, slightly convex, thin, translucent; suture slightly incised. Surface without axial sculpture apart from wide thickened rib near lip. Spiral sculpture of weak band just below suture. Remaining whorls smooth apart from basal cords, clearly present on last whorl, extending to just below adapical end of columella. Aperture rather wide, 38–42% of shell height. Outer lip thickened, bearing continuations of basal cords on abapical end. Inside denticulate with weak sinus on adapical end. Up to 6 denticles, adapically stronger. Columellar callus thick with row of slightly merged denticles, abapically stronger. Parietal callus rather thick. Siphonal canal very short, half-open, slightly recurved. Teleoconch whorls yellow-brown, with network of irregular white spots. Protoconch white to off-white with darker nucleus. Aperture and columella white. Radula not studied. Height of holotype: 5.0 mm. Remarks. This species is a member of the Mitrella philia (Duclos, 1846) complex. Species within this complex are all of about the same size, have the same general shell morphology with an incised suture and paucispiral protoconch (see also Monsecour & Monsecour 2024). However, Mitrella harryleei differs from M. philia (figs 2 G–H) by its slightly smaller size, its thinner translucent shell, less incised suture, more bulbous protoconch, slightly longer sihonal canal and different color pattern. Mitrella harryleei also differs from Mitrella goubini (Hervier, 1900) (erroneously considered a synonym of M. philia) (figs 2 I–J) by its slightly smaller size, thicker shell, with different type of protoconch and spire, lower number of teleoconch whorls and different color pattern. The genus Mitrella has proven highly polyphyletic (deMaintenon & Strong 2022) and the Mitrella philia species complex will most likely be transferred to another genus in the future. Etymology. Named after the late Harry Lee, Florida, USA, for his career as an expert amateur malacologist.