Leucosyrinx urbanae Kantor, Fedosov & Puillandre, 2025, sp. nov.

Leucosyrinx urbanae sp. nov. urn:lsid:zoobank.org:act: F3094F19-FFC7-46AF-9DBA-9B9E0EAFD084 Figs 10D–E, 13A–D Etymology The species is named after Danièle Urban-Dehoux, a volunteer of many years of the malacological team of the MNHN. Material examined Holotype (sequenced) SOLOMON ISLANDS • E of Malaita; 8°41′ N, 161°04′ E; depth 556–864 m; SALOMONBOA 3, stn CP2800; MNHN-IM-2009-18962. Other material (all sequenced) PAPUA NEW GUINEA • 1 lv; East of Manus I.; 2°11′ S, 147°18′ E; depth 499–517 m; BIOPAPUA, stn CP3691; MNHN-IM-2009-17215. SOLOMON ISLANDS • 1 lv; NW Santa Isabel I.; 7°42′ S, 157°44′ E; depth 550–682 m; SALOMON 2, stn CP2214; MNHN-IM-2007-42510. Description MEASUREMENTS (holotype). SL 14.2 mm, AL (with canal) 7.6 mm, AL (without canal) 4.0 mm, SW 4.0 mm. SHELL (holotype). Shell small, narrow fusiform, with moderately high spire, very light tan in color, thin, semitransparent, fragile. 7.5 teleoconch whorls with distinctly angular rounded shoulder and weakly concave subsutural ramp. Paucispiral, small protoconch of about 1.75 convex evenly rounded whorls, light brownish, protoconch–teleoconch transition indiscernible due to shell erosion. Shallow, impressed suture. Strong, oblique, narrow, and rounded axial folds on shoulder of teleoconch whorls, increasing in number from 9 on first whorl to 11 on penultimate and 12 on last whorls. Folds fade on subsutural ramp, reach lower suture on upper whorls, disappear below shoulder on last whorl. On posterior half of last whorl folds progrwessively weaken, although still visible.Very weak spiral sculpture, hardly discernible on subsutural ramp and below shoulder on last whorl, of irregularly spaced low cords, slightly better pronounced on transition to canal. Numerous thin, visible on subsutural ramp growth lines. Shell base weakly convex, smooth transition to long and straight canal. Narrow, elongate-oval aperture, poorly differentiated from canal, inner lip nearly straight, outer lip very thin and fragile. Columellar and parietal sides with narrow, distinct callus, of same color as remaining part of last whorl. Moderately deep, subsutural, broadly arcuate anal sinus extends across subsutural ramp, confluent with large forward extension of outer lip. RADULA (Fig. 10D–E; studied in MNHN-IM-2009-17215). Marginal teeth duplex, ~190 µm in length (5.1% AL without canal). Major limb lanceolate in dorsal view, curved. Accessory limb relatively broad, at tooth base equals total tooth width, ~0.75 of total tooth length, inserted into distinct deep socket on dorsal side of major limb. DNA diagnosis (based on 3 cox 1 sequences) ‘C’ in site 43, ‘T’ in site 412, ‘C’ in site 541. Remarks The two other specimens are similar to the holotype in shell outline and axial sculpture. The specimen MNHN-IM-2009-17215 (Fig. 13D) has a much better pronounced spiral sculture of closely spaced rounded cords, visible also on the subsutural ramp. Conchologically it is similar to Leucosyrinx sp. 23 and, particularly, to L. gaelae sp. nov, differing in their smaller size and a longer siphonal canal, but they are phylogenetically not closely related. Distribution Solomon Is., Papua New Guinea, 499– 556 m.