Bellaspira aurantiaca, 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 : 26

Bellaspira aurantiaca , new species

( Plate 5 )

Type material. Holotype 10.3 x 4.6 mm, B. Schilling! Jan 1984 (UF 355560). 7 paratypes: 3 spec., 9.4 x 4.1, 5.4 x 2.8 & 4.2 x 2.3 mm, in 55 m, 40 km SE of Pensacola, B. Schilling! Jan 1984 (UF 355564); 2 spec., 11.2 x 4.6 & 5.8 x 3.1 mm, in 71–74 m, Bouma Bank, Louisiana, 28°03.439'N, 092°26.978'W, E. García! aboard R/V Pelican, 30 Jun 2001 (EFG 23280); 1 spec., 11.4 x 4.5 mm, in 100 m off Alabama, 29°14'N, 88°16'W, E. García! aboard R/V Pelican, 16 Oct 1994 (EFG 14577); 1 spec., 10.6 x 4.4 mm, in 26 m off Destin, Okaloosa Co., W Florida, T.L. Moise! Oct 1951 (ANSP 194052).

Type locality. 4 km SE of Pensacola, Escambia Co., W Florida, in 55 m depth.

Other material examined. An additional 11 specimens were examined: 3 spec., 10.0 x 4.2, 8.9 x 4.1 & 8.7 x 4.1 mm, in 88 m, Ewing Bank, Louisiana, 28°4.57'N, 090°59.99'W, E. García! aboard R/V Pelican, 4 Jul 2003 (EFG 24651); 1 spec., 9.0 x 3.7 mm, in 60–70 m, Sackett Bank, Louisiana, 28°38.16'N, 089°33.19'W, E. García! aboard R/V Pelican, 7 Jun 2004 (EFG 25191); 1 spec., 9.1 x 4.3 mm, in 140 m, off Alabama, 29°21'N, 87°42'W, E. García! aboard R/V Pelican, 15 Oct 1994 (EFG 14539); 2 spec., 7.9 x 3.5 & 7.8 x 3.5 mm, in 55 m, SW of Panama City, Bay Co., W Florida, J. Moore! 1965 (EFG 11797); 1 spec., 7.8 x 3.4 mm, in 55 m, Cedar Keys, Levi Co., W Florida (USNM 900085); 3 spec., 6.9 x 3.1, 6.5 x 3.3 & 5.7 x 2.9 mm, in 183–213 m, SE of Looe Key, Florida Keys, J. Moore! Sep 1964 (USNM 900240).

Range and habitat. Louisiana; Alabama; W Florida (off Escambia Co.; off Okaloosa Co.; off Levi Co.); Florida Keys (off lower Keys). Most depth reports are between 50–100 m, exceptionally as shallow as 26 m and deep as 183 m.

Description. Shell small (to 11.4 mm), stoutly fusiform, truncated anteriorly; up to a total of 8 whorls, moderately convex to swollen, sutures impressed, undulant over and under rib terminations, last whorl large, approximately 64% of total shell length. Protoconch of approximately 1½–1¾ glossy-smooth, round whorls. Axial sculpture of prominent, oblique ribs that run suture-to-suture and evanesce low on the shell base, their interspaces wider than the ribs; 5–8 ribs on penultimate, 3–6 on last whorl to the varix. Rib crests round. Ribs tend to align but vary among individuals from fully aligned to offset, especially on last whorl. Growth striae microscopic. Varix is an expanded last rib, within ⅓-turn of outer lip’s edge, not always in alignment with previous whorl’s rib. Spiral sculpture of closely spaced threads over entire teleoconch, made jagged by growth striae; somewhat coarser threads are more widely spaced on anterior fasciole. Sulcus absent; somewhat reduced and slightly curved ribs are the only trace of the anal sinus. Outer lip thin, usually without axial folds; edge forming a low arc from anal sinus to end of the anterior canal. Stromboid notch weak. Anal sinus a wide but shallow indentation of outer lip’s edge when shell is viewed laterally; aperture an inverted V-shape at the junction of the inner and outer lips when shell is viewed ventrally; callus present on parietal wall, and inside of outer lip in sinus of older specimens. Inner lip recumbent, margined and edge slightly erect on anterior canal, not margined on parietal wall, ending in a low callus posteriorly. Anterior canal short, wide, open, and turned to the left when viewed ventrally; notch present on its end; anterior fasciole not swollen. Color off white with a variable central brownish orange band that may cover the entire whorl except for rib crests, or be reduced to a just the rib interspaces.

Remarks. Taxonomy. Bellaspira aurantiaca has all the principal characteristics of the genus, including the typical anal sinus, ribs suture-to-suture, varix represented by an enlarged rib, and spiral incised lines overall. Unique to this species is the presence of relatively coarse spiral threads (consequently shell surface is not glossy) and brownish-orange shell color pattern. Variability. The average length of 19 measured specimens is 8.24 mm (4.2–11.4 mm) and their average W/L is 0.460. Observed variation occurs principally in color and the arrangement of ribs. Color varies from pure white to almost completely brownish orange. The brownish orange may appear in a solid spiral band, or be confined to just the rib interspaces. Rib arrangement may be strictly aligned as is usually the case in B. pentagonalis (Dall, 1889) , or unaligned. Identification. This species is recognizable by its brownish orange color and whitish ribs. It differs from B. pentagonalis in possessing coarser spiral microsculpture (the shell is not as glossy) and a different coloration. From B. amplicostata , new species, it differs in possessing fewer and narrower ribs, and a different coloration.

Etymology. The Orange-colored Bellaspira , from the Latin adjective aurantiacus, feminine aurantiaca , meaning orange-colored. Named after the unique and outstanding feature of this species—its color.

Figures

PLATE 5. Bellaspira aurantiaca, new species. Upper panel. Fig. 1, Holotype, SE of Pensacola, Escambia Co., W Florida (UF 355560), ventral, lateral & dorsal, views. Lower panel, examples of variability in form and color. Fig. 2: paratype from type locality (UF 355564); Fig. 3: paratype, Bouma Bank, Louisiana (EFG 23280); Figs. 4 – 6: SE of Looe Key, Florida Keys (USNM 900240); Fig. 7: off Cedar Keys, Levi Co., W Florida (USNM 900085); Fig. 8: Sackett Bank, Louisiana (EFG 25191), an all-white form. Figs. 9 – 10: paratype, Bouma Bank, Louisiana (EFG 23280), ventral view (Fig. 9) and apical view showing varix aligned with previous whorls’ ribs (Fig. 10); Figs. 11 – 12: paratype, off Destin, Escambia Co., W Florida (ANSP 194052), ventral view (Fig. 11) and apical view showing penultimate whorl with 8 ribs (Fig. 12); Figs. 13 – 14: Ewing Bank, Louisiana (EFG 24651), ventral view (Fig. 13), and apical view showing varix not aligned with ribs (Fig. 14); Fig. 15: SW of Panama City, Bay Co., W Florida (EFG 11797); Figs. 16 – 17: paratype, offshore, Alabama (EFG 14577), ventral view (Fig. 16) and apical view showing varix almost aligned (Fig. 17).