Calliclava fasciata, 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 : 47-48

Calliclava fasciata , new species

( Plate 17 )

Type material. Holotype, 16.1 x 6.0 mm (UF 470272); 2 paratypes: 1 spec., 17.3 x 6.6 mm, in 6 m, Los Roques, Venezuela (USNM 1291323); 1 spec., 17.6 x 6.8 mm, in 22–25 m, off Cabo Codera, Miranda State, Venezuela (P. Stahlschmidt coll.).

Type locality. Arenas Point, Tortuga I., Venezuela, in 8 m.

Range and habitat. Venezuela ( Tortuga I.; Los Roques Is.). If the specimen depicted in Daccarett & Bossio (2011, species 787) is this species, then its range would include Colombia. Specimens from Venezuelan localities were taken from 6–25 m depths. The Colombian specimen, if proven to be this species, was reported from 44 m.

Description. Shell small (to 17.6 mm total length), fusiform, glossy, translucent between ribs and spirals; whorls convex, about 10½ total, the last approximately 56% of total length; sutures impressed; principal sculptural element of ribs and spiral threads. Aperture narrow, widest posteriorly near anal sinus. Protoconch approximately 2¼–2½ translucent whorls, a clearly visible carina present on both whorls beginning mid-whorl on the first, subperipheral beginning on 2nd to end of protoconch. Axial sculpture of numerous narrow, opisthocline ribs, that extend from suture-to-suture, are recurved in sulcus, and run to anterior fasciole on last whorl; whorls number 14– 16 on penultimate, 9–12 on last whorl to varix; rib interspaces much wider than ribs. Growth striae present over entire shell, most visible between spiral threads. Varix broad, hump-like, approximately ⅓-turn from edge of outer lip. Spiral sculpture of flattened threads, interspaces less than thread width, or alternatively, wide grooves evenly spaced creating the appearance of flattened threads, closer and narrower in sulcus; threads override axials giving them a somewhat nodulose appearance; threads number 6 on penultimate and 15 on last whorl to anterior fasciole. An additional 7 present on fasciole. Sulcus convex, about ¼- to ⅓-whorl height with 3 spiral threads in addition to axial ribs that are narrowed, educed, and recurved. Outer lip flattened from varix to edge of lip thus projecting out from the circumference of the shell in apical view; with 4 axial folds; lip edge forms a flat arc from anal sinus to the stromboid notch. Stromboid notch deep, edge flared. Anal sinus deep, positioned whorl shoulder, U-shaped, entrance slightly constricted by callus on parietal wall; upward flare of sinus edge and outward curve of outer lip gives the appearance of being spout-like. Inner lip erect anteriorly, recumbent and wider on parietal wall, and formed into a lobe posteriorly; incremental growth layers visible at edge of lip. Anterior canal open, narrow, moderately long, turned to the right when viewed ventrally, upturned slightly at its tip, and notched. Anterior fasciole not swollen. Color white with a wide yellow-brown band mid-whorl, which appear on the bottom half of spire whorls, and darker brown patch on varix. Aperture light violet, which shows through the outer lip.

Remarks. Taxonomy. Calliclava fasciata has all of the characteristics of the genus: numerous ribs that extend from suture-to-suture with a distinctly demarcated sulcus, conspicuous spiral threads across intercostal spaces, and a protoconch with both whorls carinate. Variability. The 3 specimens have an average total length of 17.00 mm (16.1–17.6 mm) and an average W/ L ratio of 0.377. Identification. Calliclava fasciata is similar to C. vigorata , new species. It is somewhat larger (17.00 versus 13.11 mm average total length), has a yellow-brown mid-whorl band ( C. vigorata is usually white), and not as stout (average W/L = 0.377 versus 0.399). From C. tobagoensis , new species it differs in size, coloration, and minor details of surface sculpture. Calliclava fasciata is larger (17.0 versus 10.8 mm average total length), and has a white shell with a wide, mid-whorl spiral band of color; C. tobagoensis has a more uniformly colored shell with maculation in the intercostal spaces on the whorl shoulders.

Etymology. The Banded Calliclava ; named for the prominent yellow-brown mid-whorl spiral band present on all specimens examined. From the Latin adjective fasciata meaning having a band.

Figures

PLATE 17. Calliclava fasciata, new species. Figs. 1 – 3: holotype, Arenas Point, Tortuga I., Venezuela (UF 470272). Fig. 1: ventral, lateral & dorsal views; Fig. 2: enlarged view of protoconch (not to scale); Fig. 3: apical view, V = varix, L = edge of outer lip. Fig. 4: paratype, Los Roques, Venezuela (USNM 1291323).