Leiosyrinx apheles, Bouchet & Sysoev, 2001

Bouchet, P. & Sysoev, A., 2001, Typhlosyrinx - like tropical deep-water turriform gastropods (Mollusca, Gastropoda, Conoidea), Journal of Natural History 35 (11), pp. 1693-1715 : 1710

Leiosyrinx apheles n. sp.

(figures 40, 41)

Type material. Holotype MNHN.

Type locality. Indonesia, Strait of Makassar, 00°31'N, 117°50'E, 595 m [ C orindon, sta. CH 214 ].

Material examined. Philippines. Musorstom 2: Sta. CP55 , SW of Luzon I., 13°54.1'N, 119°58'E, 865 m, one dd (figure 41) . Indonesia. Corindon: Sta. CH 214 , Makassar Strait, 00°31'N, 117°50'E, 595 m, one dd (holotype, figure 40) .

Distribution. Philippines and Indonesia, shells in 595– 865 m.

Description. Holotype (figure 40). Shell slender, rather thin and fragile, slightly translucent, polished, spire occupying 38% of total shell height. Apex dissolved, protoconch missing, fi rst teleoconch whorls and parts of later whorls corroded. Teleoconch whorls ca 9.5, suture shallow, impressed, whorls weakly convex, periphery in lower third. No axial sculpture except incremental lines. Spiral sculpture consisting only of about 15 cords on canal, cords separated by narrow interspaces, more closely set towards end of canal. Aperture narrow, inner lip very weakly curved, columellar part long, almost straight. Anal sinus deepest just below suture, very broad but shallow, outer lip strongly projecting below sinus. Canal rather short, narrow, poorly differentiated from shell base. Colour light brownish orange.

Dimensions: shell height 25.8 mm, last whorl height 16.0 mm, aperture height 13.1 mm, diameter 8.4 mm.

The specimen from the Philippines (figure 41) is 30.3 ✕9.0 mm at 9.8+ whorls (apex dissolved). It differs from the holotype in having a relatively higher spire (42% of total shell height), and in its shining greyish white colour.

Remarks. Leiosyrinx apheles is super fi cially similar to L. matsukumai ; the two species co-occur in the Philippines, but L. apheles lives in deeper water. L. apheles differs from L. matsukuma i by its much more fragile and slender shell, lower position of whorl periphery, shallower and broader sinus, and weaker sculpture con fi ned to a few cords on canal only. The protoconch and fi rst teleoconch whorls are dissolved in both specimens of L. apheles available.

Etymology. From the Greek apheles (adj.), meaning smooth, simple, with reference to the strongly reduced sculpture.