Austrofusus (Neocola) ngatuturaensis n. sp. (Figs. 57 and 58).
This species resembles A. taitae (Marwick) and also shews possible alliance to A. gamma Finlay.
Shell moderately small, fusiform with conical spire stepped on account of strongly angled whorls and a little less in height than aperture and canal. Six or seven whorls with high, fairly smooth protoconch (about 3½ whorls) shewn moderately well on paratype. Whorls concave on shoulder, with suture margined by 2 close-spaced strong cords on narrow raised shoulder, and corrugated as result of strong axial costae. Costae faint on excavated shoulder and raised into sharp tubercles on angle, though dying away gradually on base. Earliest spire-whorls convex, later ones have angle-keel about middle. Body-whorl also with faintly nodular lower keel giving more definite bi-angular outline than in taitae.
Aperture oval, oblique, narrowly notched above on account of appressed shoulder, and angled about middle. Outer lip thin and
with strong transverse lirae within. Inner lip thin and narrowly limited. Columella has greater twist to left and back than in typical Austrofusus with very narrow and only slightly raised marginal keels to fascicle.
Spiral ornamentation of strong approximately equidistant, sharply-raised lirae surmounting the costae and their nodular extensions, and generally with 1, sometimes 2, or, on the base, even more, subsidiary threads in the interspaces. Two close-spaced lirae, with a fairly strong intermediate secondary, make a distinct keel at the shoulder-angle, whilst the lower keel of the body-whorl has a single strong spiral rib.
The central basal area has 3 or 4 strong spiral cords, with the usual intervening secondary threads, and is inclined to be finely nodular. Below these there is similar, but less prominent spiral sculpture. Oblique growth-lines may produce a faint reticulation with the spiral lirae.
Dimensions of holotype (incomplete): 24 mm. × 14.8 mm. Paratype: 23 mm. × 13 mm.