Revised descriptions of New Zealand Cenozoic Mollusca from Beu and Maxwell (1990)
(Pl. 48p): Murdoch's (1924) figured syntype, "blue sandy clays, Castlecliff", Wanganui, Castlecliffian (TM6837, GNS)
Beu & Maxwell (1990): Chapter 16; p. 361; pl. 48 p.
Synonymy: Verconella marshalli Murdoch 1924, p. 159; Aeneator drewi Fleming 1943, p. 200 (a monstrosity); probably = the Recent A. marshalli separabilis Dell 1956c, p. 98, and likely most of the other names proposed for shallow-water Aeneator species.
Type species of Aeneator Finlay, 1926
Description: Large for genus (60-80 mm high), with moderately tall spire and long, straight anterior canal, evenly and strongly inflated whorls, broad, shallow sinus in outer lip over sutural ramp, and anteriorly expanded, lightly thickened outer lip with many long, narrow ridges inside. Spiral sculpture of many narrow, close primary cords with several intermediate threads in each interspace, crossed by low, rounded axial costae on spire whorls, fading out before last whorl of large shells. Aperture large, oval; inner lip with 1 or 2 low ridges on parietal swelling, and (in large shells) many low nodules along left edge of columellar lip. Protoconch dome-shaped, relatively small, of 2.5 smooth, inflated whorls, with low costae on last half-whorl.
Comparison: The modern form named Aeneator marshalli separabilis by Dell (1956c, p. 98) differs from typical Castlecliff fossils of A. marshalli only in its shorter spire and sparser, more prominent axial costae. Too few modern specimens are known to be able to evaluate its status, but it is certainly closely similar to the short, costate form of A. marshalli found in late Nukumaruan siltstone in central Hawke's Bay, and even the modern species(?) A. otagoensis Finlay is conceivably part of the variation of A. marshalli. The protoconch is much smaller than in the similar genus Penion. The holotype of A. drewi is a specimen of A. marshalli with irregular growth following a healed injury. The restricted early Castlecliffian species A. delicatulus has much finer spiral sculpture than A. marshalli; the Castlecliffian-Recent form A. attenuatus differs mainly in its taller spire, and seems likely to be part of the variation of A. marshalli. The early Nukumaruan species A. imperator (Wairarapa-North Canterbury) has much coarser spiral and axial sculpture than A marshalli.
Distribution: Nukumaruan-Castlecliffian (-Recent?); Castlecliff, Wanganui, Castlecliffian (types of Verconella marshalli and Aeneator drewi); Recent, Ohope Beach, Whakatane (type of A marshalli separabilis). A common fossil in offshore siltstone facies, deposited in mid-outer shelf depths, in Wanganui basin, Hawke's Bay, Wairarapa, and North Canterbury.
Cite this publication as: "A.G. Beu and J.I. Raine (2009). Revised
descriptions of New Zealand Cenozoic Mollusca from Beu and Maxwell (1990). GNS
Science miscellaneous series no. 27."
© GNS Science, 2009
(Included with a PDF facsimile file copy of New Zealand Geological Survey Paleontological Bulletin 58 in CD version from: Publications Officer, GNS Science, P.O. Box 30368 Lower Hutt, New Zealand)