Leptadrillia luciae, Fallon, Phillip J., 2016

Fallon, Phillip J., 2016, Taxonomic review of tropical western Atlantic shallow water Drilliidae (Mollusca: Gastropoda: Conoidea) including descriptions of 100 new species, Zootaxa 4090 (1), pp. 1-363 : 226-227

Leptadrillia luciae , new species

( Plate 112 )

Type material. Holotype 11.0 x 3.7 mm (USNM 1199828); 4 paratypes from the type locality: 10.1 x 3.3, 10.0 x 3.1, 8.8 x 3.0 & 7.8 x 2.6 mm (USNM 1199872). All from inside beer bottles retrieved by M. Harasewych! aboard submersible Curasub , 23 May 2012.

Type locality. Off Sea Aquarium, Bapor Kibra, Willemstad, Curaçao, Netherlands Antilles, 12°04.87'N, 68°53.75'W, in glass bottles collected at 130– 168 m.

Range and habitat. Known only from the type locality. Empty shells collected from in bottles at 130–168 m depths.

Description. Shell small (to 11.0 mm in total length), glossy, semi-translucent, narrowly fusiform with a long anterior canal and surface sculpture of axial ribs; whorls slightly convex, their peripheries are anterior to whorl midpoints appearing to “sag” near the suture of succeeding whorl; whorls total up to 9, the last about 59% of total length. Protoconch of 2 smooth, translucent whorls; tip of first partially immersed. Axial sculpture of narrow ribs that run from suture-to-suture on spire whorls, to anterior fasciole on last, number 9 on penultimate and 8 to varix on last whorl; ribs recurved on shoulder, sigmoidal on last whorl; interspaces about as wide as their width; rib crests round. Vari x rather large, protruding, broader and higher than preceding ribs; straight, not sigmoidal. Spiral sculpture absent except for approximately 12 faint threads on and adjacent to anterior fasciole. Sulcus obscure; ribs and growth striae on shoulder recurved, reflecting outline of the anal sinus. Outer lip missing on all specimens in hand, which were collected as empty shells. Anal sinus also missing, but which may not have been fully developed on these specimens, which appear juvenile as there is no sign of the development of a callus on the parietal wall. Inner lip narrow, thin, unemarginate. Anterior canal long, open; fasciole not swollen. Color base tan with a subsutural light golden brown band; varix also light golden brown.

Remarks. Taxonomy. Leptadrillia luciae has all of the characteristics of the genus: a spindly shell with a long anterior canal, ribs that extend from suture-to-suture, no sulcus, and no spiral sculpture except for threads near and on the anterior fasciole. This species may be unique for the large size of its large varix. Variability. The average total length of five specimens is 9.54 mm (7.8–11.0 mm); their average W/ L ratio is 0.329. The faded condition of available specimens precludes assessment of the variability in color pattern. Identification. Leptadrillia luciae is very close in color pattern and size to L. incarnata , new species but differs in possessing less convex ribs with whorl peripheries closer to the sutures, a broader yellow-brown shoulder band, and a larger varix. Color has mostly faded in the dead-collected paratypes, but a trace of the band is still visible. The color pattern differentiates this species from all other Leptadrillia . From L. splendida Bartsch, 1934 it also differs in possessing less convex whorls and straighter ribs. From L. flavomaculata , new species it differs in having broader ribs and shell (W/ L ratio is 0.329 versus 0.313).

Etymology. Lucy’s Leptadrillia ; named after my granddaughter, Lucy Lillian Fallon, who arrived just days before completing this species’ description.

Figures

PLATE 112. Leptadrillia luciae, new species. Figs. 1 – 3: holotype, off Sea Aquarium, Curaçao (USNM 119982). Fig. 1: ventral, lateral & dorsal views; Fig. 2: enlarged view of protoconch (not to scale); Fig. 3: apical view, V = varix. Fig. 4: paratype, from the type locality (USNM 1199872).