Revised descriptions of New Zealand Cenozoic Mollusca from Beu and Maxwell (1990)
(Pl. 26j): GS3245, Q8/f9687, Pakaurangi Member, Pakaurangi Point, Kaipara Harbour, Altonian (GNS)
Beu & Maxwell (1990): Chapter 11; p. 237; pl. 26 j.
Synonymy: Bathytoma bartrumi Laws 1939a, p. 496; Bathytoma (Bathytoma) bartrumi, Beu & Maxwell 1990, p. 237, pl. 26m.
Classification: Conidae: "Clathurellinae" clade 20 (Puillandre et al. 2008)
Description: Rather large for genus (height 35-60 mm), biconic, spire about half total height. Protoconch conical, of 3 whorls, last fifth of a whorl with opisthocyrt costellae, remainder smooth. Teleoconch of 8-9 whorls, sharply angled well below middle on spire, sutural ramp steep, almost flat; last whorl weakly excavated. Axial sculpture of prominent blunt tubercles on periphery, tending to become obsolete on last whorl (14-18 per whorl); numerous short and fine costellae just below suture; and fine growth lines. Spiral sculpture of fine threads on ramp and moderately strong, narrow, granulose cords with finely nodulose interstitial threads below, about 8 cords on last whorl and numerous fine, irregular threads on fasciole. Aperture narrow, elongate, siphonal canal short, scarcely differentiated, shallowly notched; fasciole rounded. Columella almost straight except for blunt twist. Inner lip callus moderately thick over columella, thin above; outer lip thin, weakly crenulate, with a deep slot-like anal sinus on peripheral keel.
Comparison: Bathytoma bartrumi is readily distinguished from B. haasti (Pl. 22m) by having relatively sparse and much stronger peripheral tubercles. B. finlayi (Altonian-Lillburnian, Clifden) has more numerous peripheral nodules (21-25 per whorl), and more widely spaced and more strongly nodulose spiral cords than B. bartrumi.
Distribution: Otaian-Altonian, Pakaurangi Formation, Pakaurangi Point (type), uncommon.
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)