Leucosyrinx schepmani, Kantor & Fedosov & Puillandre, 2025

Kantor, Yuri I., Fedosov, Alexander & Puillandre, Nicolas, 2025, Revision of the Indo-Pacific species of the genus Leucosyrinx Dall, 1889 (Neogastropoda: Conoidea: Pseudomelatomidae), European Journal of Taxonomy 999, pp. 1-126 : 27-29

Leucosyrinx schepmani sp. nov.

urn:lsid:zoobank.org:act:AF034A13-FDE2-4EEF-9F40-FF30BF35D7DA

Fig. 9A–F

Etymology

The species is named after Mattheus Marinus Schepman, famous Dutch malacologist for his contribution to the study of deep-water gastropods, including Conidae , who described several species of Leucosyrinx .

Material examined

Holotype (sequenced)

SOLOMON ISLANDS • Santa Isabel I.; 8°47′ N, 159°38′ E; depth 762–1060 m; SALOMON 2, stn CP2182; MNHN-IM-2009-16761.

Other material (all sequenced)

PAPUA NEW GUINEA • 1 lv; New Ireland; 2°42′ S, 150°02′ E; depth 827–966 m; KAVIENG 2014, stn CP4483; MNHN-IM-2013-58844 .

PHILIPPINES • 2 lv; Luzon I.; 15°45′ N, 121°45′ E; depth 562 m; AURORA 2007, stn CP2663; MNHN- IM-2009-13432, IM-2009-13433 • 1 lv; Luzon I.; 15°53′ N, 121°54′ E; depth 518–538 m; AURORA 2007, stn CP2750; MNHN-IM-2009-13464 .

SOLOMON SEA • 1 lv; Induna I.; 4°35′ S, 152°25′ E; depth 575–616 m; MADEEP, stn CP44266; MNHN-IM-2013-45461.

Description

MEASUREMENTS (holotype). SL 33.0 mm, AL (with canal) 14.4 mm, AL (without canal) 10.0 mm, SW 9.8 mm.

SHELL (holotype). Shell medium-sized, thin, elongate fusiform, slender, with high spire, uniformly light tan in color. 9.75 distinctly roundly angled at shoulder teleoconch whorls, with slightly concave, nearly straight subsutural ramp. Paucispiral protoconch of about 1.5 evenly rounded bulbous whorls, light brown. Posterior part of protoconch and first teleoconch whorl eroded protoconch–teleoconch transition indistinct is indistinct. Shallow, impressed suture. 12 distinct, oblique, narrow, and rounded axial folds on shoulder of last whorl and 12 on penultimate whorl. Folds fade on subsutural ramp, hardly reach lower suture on penultimate whorl, equally pronounced on all teleoconch whorls. Very weak spiral sculpture of low, rounded, and narrow cords, with interspaces exceeding cords width, absent on subsutural ramp, visible below shoulder. Numerous thin, prominent on subsutural ramp growth lines. Shell base weakly curving, smooth transition to long, straight rather broad canal. Narrow, elongate-oval aperture, poorly differentiated from canal, outer lip fragile, partially broken. Inner lip slightly concave, nearly straight. Columellar and parietal sides with narrow, distinct callus, of same color as the 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. Not examined.

DNA diagnosis (based on 6 cox 1 sequences)

‘C’ in site 250, ‘C’ in site 463, ‘A’ in site 508.

Remarks

The other studied specimens are generally rather similar to the holotype in shape and sculpture pattern. The most variable character is the convexity of the last whorl. Spiral sculpture is more variable and some specimens have rather distinct spiral cords, visible even on subsutural ramp (e.g., in MNHN- IM-2009-13432 from the Philippines – Fig. 9F ).

The species is very similar, hardly distinguishable conchologically from L. oliverioi sp. nov., but they are not sister species.

Distribution

Philippines, Solomon Sea, Papua New Guinea, 518– 827 m.

Figures

Fig. 9. A–F. Leucosyrinx schepmani sp. nov. A–C. MNHN-IM-2009-16761, holotype, SL 33 mm. D. MNHN-IM-2013-58844, Papua New Guinea, 827–966 m, SL 34.4 mm. E. MNHN-IM-2009-13464, Philippines, 518–538 m, SL 28.8 mm. F. MNHN-IM-2009-13432, Philippines, 562 m, SL 30 mm. G–L. Leucosyrinx oliverioi sp. nov. G–I. MNHN-IM-2007-17928, holotype, SL 37.5 mm. J. MNHN- IM-2009-17078, Papua New Guinea, 490–715 m, SL 33.6 mm. K–L. MNHN-IM-2007-17690, Vanuatu, 667–750 m, SL 32.7 mm. All shells at the same scale.