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

Leucosyrinx vanweddingenae sp. nov. urn:lsid:zoobank.org:act: F4AD5344-967D-4CC8-A0FA-58341D58195A Fig. 7I–M Etymology The species is named after Mélanie van Weddingen, member of the ERC “HYPERDIVERSE” team, for her contribution to the management of the neogastropod collection of the MNHN. Material examined Holotype (sequenced) SOUTH MADAGASCAR • 1 lv; 25°43′ S, 44°24′ E; depth 729–732 m; ATIMO VATAE, stn CP3597; MNHN-IM-2009-14918. Other material (sequenced) MADAGASCAR • 1 lv; off Majunga; 15°22′ S, 45°58′ E; depth 650–850 m; MIRIKY, stn CP3252; MNHN-IM-2009-16909. Description MEASUREMENTS (holotype, largest specimen). SL 27.1 mm, AL (with canal) 12.5 mm, AL (without canal) 8.5 mm, SW 9.3 mm. SHELL (holotype). Small, narrow fusiform, with high spire, rather strong, uniformly off white. 8.5 teleoconch whorls. Paucispiral, bulbous, light tan protoconch, of about 1.75 rounded whorls. Protoconch–teleoconch transition indistinct, marked by appearance of shoulder keel. Teleoconch whorls markedly angled at shoulder, with distinctly concave subsutural ramp. Distinct, shallow, impressed suture. 15 strong, weakly oblique, broad, rounded axial folds on last whorl and 14 on penultimate whorl, with intervals slightly broader than folds. Folds fade on sharply delimitated subsutural ramp, slightly weaken towards lower suture, folds disappear on last whorl periphery. Very weak spiral sculpture of rounded, narrow, equally developed cords on periphery of last whorl and shell base, indiscernible on subsutural ramp, around 20 on periphery, shell base and canal. Intervals between cords uneven, 1–3 times cords’ width. Numerous weak, thin growth lines. Shell base slightly convex, weakly curving, smooth transition to medium long and straight canal. Narrow, elongate-oval aperture, poorly differentiated from canal. Inner lip nearly straight. Columellar and parietal sides with narrow, distinct callus. Moderately deep, subsutural, broadly arcuate anal sinus extends across subsutural ramp, confluent with large forward extension of outer lip. RADULA. Not examined. DNA diagnosis (based on 2 cox 1 sequences) ‘T’ in site 74, ‘A’ in site 346, ‘A’ in site 508, ‘C’ in site 640. Remarks Only two specimens are available. The second specimen (MNHN-IM-2009-16909) is similar to the holotype, but the axial folds disappear in the last half of the last whorl. The subsutural ramp has indistinct spiral striation. The species is very similar to L. ringevali sp. nov., which was collected in close proximity at similar depths, but differs in a much weaker spiral sculpture, which in L. ringevali consists of much more numerous, distinct and uniformly closely spaced cords. Besides, according to the phylogenetic tree, the species are not closely related. There is a certain similarity to L. derzellei sp. nov., but the new species differs in a smaller and paler shell and in much weaker spiral sculpture. Distribution Madagascar, 650– 729 m.