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

Leucosyrinx herosae sp. nov. urn:lsid:zoobank.org:act: 7E56BC97-FC0A-46F8-B5ED-540A212407B4 Figs 15G, 19A–E Leucosyrinx sp. G – Kantor & Puillandre 2021: figs 11e, 13d–e. Etymology The species is named after Virginie Héros, a long standing member of the MNHN malacological team, in recognition of her outstanding contribution to collecting, curating and managing the molluscan collection of MNHN. Material examined Holotype (sequenced) BISMARCK SEA • N Bagabag Is; 4°44′ S, 146°11′ E; depth 540–580 m; PAPUA NIUGINI, stn CP3979; MNHN-IM-2013-19689. Other material (all sequenced) PAPUA NEW GUINEA • 1 lv; submarine mountains off Bougainville; 5°37′ S, 154°01′ E; depth 398– 399 m; BIOPAPUA, stn DW3748; MNHN-IM-2009-17089 • 1 lv; submarine mountains off Bougainville; 5°39′ S, 153°59′ E; depth 620–663 m; BIOPAPUA, stn DW3749; MNHN-IM-2009-17059 • 1 lv; New Ireland; 2°23′ S, 150°39′ E; depth 490–610 m; KAVIENG 2014, stn CP4438; MNHN-IM-2013-58314. Description MEASUREMENTS (holotype). SL 47.2 mm, AL (with canal) 22.6 mm, AL (without canal) 14.3 mm, SW 15.5 mm. SHELL (holotype). Shell medium-sized, thin but strong, glossy, fusiform, with medium high spire, uniformly light tan in color, narrow subsutural darker band. Paucispiral protoconch of about 1.5 rounded light brown whorls, protoconch–teleoconch transition indistinct due to protoconch erosion, marked by color change. 11 distinctly roundly angled at shoulder teleoconch whorls, concave subsutural ramp, nearly flat on last whorl. The suture is distinct shallow, impressed. 18 strong, oblique, broad, and rounded axial folds on body whorl, 14 on penultimate whorl. Folds fade on subsutural ramp, do not reach lower suture except upper whorls, disappear below shoulder on last whorl. Intervals between folds equal or slightly exceed folds width on last and penultimate whorls. Medium-developed spiral sculpture of distinct low, rounded, wavy, and narrow cords over entire shell, including subsutural ramp. Intervals between cords narrower than cords. Numerous and thin growth lines. Shell base rounded, convex, and passes smoothly into long, straight canal. Narrow, elongate-oval aperture, poorly differentiated from canal, inner lip nearly straight. Columellar and parietal sides with narrow, distinct callus, of same color as remaining last whorl. Deep, subsutural, broadly arcuate anal sinus extends across subsutural ramp, confluent with large forward extension of outer lip. RADULA (Fig. 15G; studied in MNHN-IM-2009-17089). Comprising about 30 rows of teeth, 15 nascent. Marginal teeth duplex, ~300 µm in length (3.2% AL without canal). Major limb broad lanceolate in dorsal view, weakly curved. Accessory limb narrow, less than half of tooth width, ~0.8 of total tooth length, inserted into distinct deep socket on dorsal side of major limb. DNA diagnosis (based on 4 cox 1 sequences) ‘A’ in site 55, ‘G’ in site 349, ‘T’ in site 478. Remarks The species resembles Leucosyrinx diomedea (Powell, 1969), nevertheless differing in a slenderer shell with a longer canal, better pronounced spiral cords on the subsutural ramp and more rounded and shorter axial folds on the shoulder. There is also superficial resemblance to Sibogasyrinx subula, easily distinguished by the radular type as well as by the presence of the row of subsutural nodules, typical of Sibogasyrinx. Distribution Bismarck Sea, Papua New Guinea, 398– 620 m.