Genus Anapepta Finlay.
Type: Admete anomala Marshall and Murdoch.
Finlay (Trans. N.Z. Inst., vol. 61, p. 241; 1930) in instituting Anapepta, allotted it subgeneric status under Inglisella. The divergent characters of the apex in the two groups seem to warrant full generic recognition for the Anapepta series of shells.
Anapepta tuberculifera n.sp. (Fig. 19).
This species is very close to A. finlayi Marwick, from Awamoa Creek. If anything, it is rather more slender, with a slightly narrower body-whorl. The anterior of the aperture is not so broadly rounded, and the canal narrower and more flexed to the left. Marwick states that finlayi has three low folds on the columella. The present species has but two, and these, though weak when seen from the front, are strong, blunt, and rounded when seen a little distance within the aperture. The embryonic and brephic sculpture of the two species is identical, but in tuberculifera two weak spirals appear on shoulder of penultimate whorl and three on shoulder of last whorl. All the spire-whorls of finlayi are biangulate; those of tuberculifera, with the exception of the first (which is biangulate), carry three strong spirals, diminishing in strength from behind. The outer lip has seven or eight lirations within.
Height, 11.0 mm.; width, 4.5 mm. (holotoype).
Locality, Clifden, Southland, new road-cutting behind race-course (type) = band 7 of the beds along the river. Also bed A, left side of river = band 6C on right side (two shells). Hutchin-sonian.
Type in writer's collection.
Anapepta explicata n.sp. (Fig. 20).
This species can at once be distinguished by the decreasing prominence of axials on penultimate whorl and their entire absence from last whorl. The protoconch is large and broad over summit, the nucleus minute and central, as described by Marwick (N.Z. Geol. Surv. Pal. Bull., No. 13, p. 122; 1931) for his A. finlayi. There is
a light shoulder slightly above middle of whorls; whorl flattish on shoulder, lightly convex below. Shoulder unsculptured except for two close, thin, spiral threads; the strongest spiral of a whorl is that at periphery, and this is slightly pinched up on summits of the axials; four or five spirals below periphery, of rather uneven strength. There are eleven axials on penultimate whorl. Body-whorl fairly full, regularly convex. Columella-plaits two, not seen from front, but situated well inside, and subequal in strength; outer lip effuse below, more so than that of tuberculifera; seven lirations within outer lip. A. anomala has heavier spirals and axials on all whorls. A. finlayi is of closely similar build, but has biangulate whorls, axials present on last whorl, and aperture more broadly rounded in front.
Height, 11.0 mm.; width, 4.8 mm.
Locality, Blue Cliffs, South Canterbury (Hutchinsonian).
Type (sole specimen) in writer's collection.
Anapepta serrata n.sp. (Fig. 21).
Easily separable on account of its heavy, sharp axial ribs on all adult whorls; the shoulder is very distinct and unsculptured; there are two thin, sharply elevated folds on columella, quite visible from the front; the lirations within outer lip are of the nature of distinct spiral threads (six in number) retreating within as far as can be seen. The structural features of the embryo are quite those of Anapepta, but it is much narrower and smaller than that of any other species so far recorded for the genus. This provides perhaps the readiest means of separation. Below the shoulder of penultimate whorl there are four thin, distant, distinct spiral threads, the posterior one considerably pinched up on surmounting axials. There are also four on body whorl between suture and shoulder, but here fine interstitial threadlets are also present. Apertural characters are those of Anapepta.
Height, 10.5 mm.; width, 4.5 mm. (holotype).
Localities—Blue Cliffs, South Canterbury (type and two paratypes); blue clays at foot of Mount Horrible, Pareora River, South Canterbury (one shell). Both are Hutchinsonian horizons.
Type in writer's collection.