Fusinus bountyi

Fusinus galatheae bountyi

DIAGNOSIS.—Relatively large, fusiform, with long anterior canal and high spire, the rather markedly angulate periphery of the whorls with pronounced nodes; with fewer and stronger tubercles on the periphery of the last two whorls than typical F. galatheae, and on the early whorls the axial ribs are more numerous and stronger.

RANGE.—Off Pitcairn Island in 26–55 fms.

DESCRIPTION.—Shell: Rather large, 116.5 to 137.7 mm (4.5 to 5.4 inches) in length, fusiform, with a high acuminate spire that comprises about 37 to 48 percent of total length, anterior neck long, narrow, and straight. Protoconch missing in all specimens, postnuclear whorls 11 in holotype, convex, with 8 ribs on 2nd postnuclear whorl, the axial ribs rapidly increasing to 10 or 11 on later whorls; ribs in earliest whorls crossed by fine spiral cords, of which the two middle ones are strongest; in later whorls the number of spiral cords increases by intercalation; beginning with the 6th whorl the ribs become angulately knobbed at the periphery; spiral sculpture crossed by very fine axial, somewhat irregular, growth lines marked (in fresh specimens) by fine periostracal lamellae which are sharply spinose at the spiral cords, giving the whole shell a densely and microscopically hirsute covering; suture closely appressed. Body whorl with 10–12 ribs that are strongly and angulately nodose at the periphery, crossed by spiral cords of varying strength, in fresh specimens covered by hairy periostracum as described above; in complete specimens the neck (enclosing the straight, relatively narrowly open anterior canal) noticeably longer than the aperture and sculptured by strong, oblique spiral cords. Aperture ovate, posteriorly acuminate, inner lip gently concave, the parietal wall curving gently into the smooth columellar portion; outer edge of parietal callus or inductura free and (in old specimens) thickened and conspicuously detached from lower part of body whorl and upper end of the neck; outer lip thickened within, marked by spiral lirae, outer edge denticulate. Operculum unguiculate, with apical nucleus and growth lines that are strongly angulate along the midline.

Radula (Figure 7): Central tooth small, with a straight horizontal base, straight inclined sides, and a rounded top; a strong, pointed, parallel-sided central cusp projects below the base, flanked on each side by another cusp of similar size and shape; also with a small pointed cusp on each outer corner of the base. Lateral teeth large, arcuate, with 15 prominent, pointed cusps, the inner one moderately large and almost straight, the outer one small and curved, the intermediate ones large, long, and rather straight except for those toward the outer edge which are incurved at their tips.

MATERIAL.—Holotype: About 1 mile off NW coast of Pitcairn Island, in 30 fms on dead coral and rubble bottom; 19 October 1967; PIT–VI:11; USNM 707230.

Paratypes: Three-fourths mile off Bounty Bay, Pitcairn, in 26–35 fms on bottom of large coral stones and rubble; 19 October 1967; PIT–VII:1; WAM 135–72. Off NW coast of Pitcairn, in 55–65 fm on bottom of stones and coral rubble; 20 October 1967; PIT–VI:19; USNM 707231. Off NW coast of Pitcairn, 40–60 fms; 20 October 1967; PIT–VI:15; BPBM 218709.

MEASUREMENTS (in mm).—