Revised descriptions of New Zealand Cenozoic Mollusca from Beu and Maxwell (1990)
(Pl. 42m): holotype of G. marwicki Beu, GS 2220, V20/f8462, Devil's Elbow, Napier- Wairoa Highway, Hawke's Bay, Nukumaruan (TM 3798, GNS)
Beu & Maxwell (1990): Chapter 15; p. 325; pl. 42 m.
Synonymy: Glaphyrina plicata Powell 1929, p. 97; Glaphyrina marwicki Beu 1965a, p. 145
Description: Large and wide for genus (36-55 mm high), with tall spire and moderately long, slightly curved canal. Whorls strongly inflated. Sculpture of many narrow, well raised spiral cords with intermediate threads, crossing very prominent, wide axial folds of evenly rounded cross-section, with evenly concave interspaces, each the same width as 1 axial fold; folds extend well down on base of whole of last whorl; all crossed by fine axial threads. Interior of outer lip lightly thickened, with many low, narrow ridges; inner lip thin, smooth. Protoconch prominent, tall, of 2 medially keeled, slightly irregular whorls, with tall, pointed apex (presumably a remnant of an only partly calcified embryonic shell) (see under G. caudata, Pl. 49j, k).
Comparison: Glaphyrina plicata differs from the more common Castlecliffian-Recent species G. caudata (Pl. 49j, k) in its wider shape, fewer and much more prominent axial folds, and straighter anterior canal. The differences between G. plicata and G. marwicki appear to be individual only. A presumed ancestral species is the uncommon, more coarsely sculptured species G. excelsa from Target Gully Shellbed, Oamaru (Altonian).
Distribution: Nukumaruan-Recent; Recent, dredged off Cuvier Island, east of Auckland (type of Glaphyrina plicata ); Devil's Elbow mudstone, top of north face of Devil's Elbow hill, Napier-Wairoa Highway, Hawke's Bay, Nukumaruan (type of G. marwicki). Widespread but uncommon in blue-grey mudstone facies in central Hawke's Bay, particularly at Devil's Elbow and in Mangatahi River near the junction with Okauawa Stream, Kereru Road (both late Nukumaruan); rare in the inner-mid shelf fauna of north-eastern North Island at present, and so apparently a warm-water species.
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)