Neodrillia albicoma (Dall, 1889) Dall, 1889

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 : 262-263

Neodrillia albicoma (Dall, 1889) , new combination

( Plate 133 )

Drillia albicoma Dall, 1889a: 83 –84, pl. 10, fig. 8. Dall (1889b: 96–97, pl. 10, fig. 8); Abbott (1974: 270, fig. 3005). Leptadrillia albicoma (Dall, 1889) : Kaicher (1984: card 3965).

Clathrodrillia albicoma (Dall, 1889) : Williams (2005; 2009 1540 [upper R photo is of USNM 87461, not USNM 159674]); García (2007: 8).

Not this species, or unconfirmed extralimital reports.

Drillia albicoma Dall, 1889 : Dall & Simpson (1901: 385 [ Puerto Rico]); Maury (1922: 149); Sander & Lalli (1982: 317 [ Barbados]); K. & L. Sunderland (1993: 14 [E Florida; photo not of this species]); Turgeon et al. (1998: 102); González (1998: [ Mexico; not figured]).

Clathrodrillia albicoma (Dall, 1889) : Rios (1983 [ Brazil]); Rios (1985: 135, pl. 46, fig. 616 [ Brazil]); Rios (1994: 159, pl. 53, fig. 707 [ Brazil]); Gracia et al. (2004: 63, fig. 43 [ Colombia; = Neodrillia princeps , n. sp.]); Rios (2009: 308, sp. 777 [ Brazil]).

Type material. Dall listed four syntypes from two different localities as this species: two from off Yucatan, Mexico, and two from off Barbados. The two from off Yucatan best match his description and figure: 24.6 x 7.5 mm (USNM 87461) and 25.7 x 8.0 mm (MCZ 7058). His description of N. albicoma matches the specimen in MCZ for size but his drawing most closely matches the specimen in USNM 87461, which is also the most complete one and has an intact protoconch. It is the best preserved specimen and the most representative specimen of the taxon, so is herein declared the lectotype. The specimen in MCZ 7058 is a paralectotype.

The two syntypes from off Barbados are believed to be an undescribed species of Neodrillia , which are described later in this work as Neodrillia crassa , new species, ( Plate 135 , Figs. 6 & 11). Their measurements are: 19.3 x 6.5 mm (USNM 87462) and 10.6 x 4.2 mm (MCZ 7059).

Type locality. R/V Blake Station 36, 23°13′N, 089°16′W [NE Campeche Bank, off Yucatan, Mexico] in 84 fms [154 m] depth.

Other material examined. One additional specimen, believed to be this species, is: 23.4 x 7.4 mm, W of Sarasota, Sarasota Co., W Florida, M.E. Powlus! 1967, ex McGinty coll. (UF 260847).

Range and habitat. Mexico (Yucatan); W Florida (Sarasota Co.). Reported at 154 m.

Description. Shell medium (to 25.7 mm in total length), fusiform, of approximately 11¾ whorls overall, the last approximately 44% of total shell length; surface dull textured, sandpaper-like to the feel; aperture narrow, only a little wider than the base of the anterior canal and anal sinus; dominant sculpture of axial ribs. Protoconch of about 1½ smooth round whorls. Axial sculpture of narrow, slightly opisthocline ribs that run from suture-to-suture on the spire, and to the anterior fasciole on the last whorl; number 15 on the penultimate and 12 on the last whorl to the varix; lower and recurved on the shoulder slope. Varix convex, wider and higher than nearby ribs but not humplike. Spiral sculpture of closely set raised threads, coarsened by fine growth striae. Sulcus concave; reduced, recurved ribs and recurved growth striae on shoulder mark progressive positions of anal sinus. Outer lip thin, juts out from base of varix; edge traces a low arc from and congruent with anal sinus to anterior canal; stromboid notch absent. Anal sinus a deep notch with flared sides, edge of outer lip turned outward just below sinus imparting a spout-like appearance. Inner lip recumbent, moderately wide, heavily enameled in older specimen, formed into a weak lobe on the parietal wall posteriorly. Anterior canal moderately long, open, turned slightly to the right when viewed ventrally; unnotched. Color white.

Remarks. Identification. Neodrillia albicoma has a shell surface microsculpture like that of Neodrillia cydia Bartsch, 1943 , the type of the genus and a distinctive characteristic of the genus. It does not have the heavy spiral sculpture of Clathrodrillia where the taxon has been placed by Williams. The assignment to Leptadrillia by Kaicher is not at all consistent with the smooth glossy surface of members of that genus. Taxonomy. Neodrillia albicoma is a deep water member of Neodrillia , with a taller spire than the type species of the genus and narrow ribs, unlike N. cydia , which inhabits the shallow sandy flats, and sand pockets of reefs. The narrow shell with a tall spire and spout-like anal sinus are distinctive. Neodrillia crassa is stouter, and with a wide pale yellow spiral band. Fenimorea pagodula is similar but has a smaller, less pronounced anal sinus, is usually colored with a broad pale yellow-orange band, and has a different shell surface microsculpture. Fenimorea petiti Tippett, 1995 is also similar but is smaller, has a more brightly colored spiral band and a different shell surface microsculpture.

Figures

PLATE 133. Neodrillia albicoma (Dall, 1889). Figs. 1 – 3: lectotype, Campeche Bank off Yucatan, Mexico (USNM 87461). 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: paralectotype, from type locality (MCZ 7058).

PLATE 135. Neodrillia crassa, new species. Upper panel. Figs. 1, 3: holotype, off Dominica (USNM 87472). Fig. 1: ventral, lateral & dorsal views; Fig. 3: apical view, V = varix; Fig. 2: enlarged view of protoconch (not to scale) of specimen in Fig. 7. Lower panel. Figs. 4 – 8, 10 – 11: paratypes. Figs. 4, 5, 7 & 10: off Sea Aquarium, Curaçao, Netherlands Antilles (USNM 1231400); Fig. 6: off Barbados (USNM 87462); Figs. 8, 9: off Holetown, Barbados (ANSP 353515 and ANSP 353514, respectively); Fig. 11: off Barbados (MCZ 7059); Fig. 12: off Barbados (MCZ 7068); Fig. 13: off Barbados (MCZ 7070); Figs. 14 – 17: off Barbados (MCZ 7069); Figs 18 – 19: off Dominica (USNM 1291373).