Bathytoma haasti

The species is moderate in size (30-55 mm) and has a biconic shape, with the spire comprising approximately 0.45-0.5 of the total height. The conical protoconch has 3.5 convex whorls, with the last 0.8 whorl featuring costellae. The teleoconch has 7-8 prominently shouldered whorls, with a concave sutural ramp. The last whorl is excavated with a short neck. Axial sculpture includes narrow tubercles on a peripheral band and sometimes prosocline ridges on the subsutural swelling, with numerous growth ridges. The penultimate whorl has 30-50 peripheral tubercles. Spiral sculpture is complex, with 2-3 narrow cords on peripheral tubercles and finer cords on the ramp, with stronger cords on the subsutural swelling. The base and upper neck have 10-15 narrow cords, with 1-3 threads between each pair; the lower neck has closely spaced cords. Most spirals are finely nodulose. The elongate aperture has a weakly twisted columella, a short, shallowly notched siphonal canal, and a thin outer lip with a broadly V-shaped anal sinus.

• Maxwell, P.A. (2009). Cenozoic Mollusca. pp 232–254 in Gordon, D.P. (ed.) New Zealand inventory of biodiversity. Volume one. Kingdom Animalia: Radiata, Lophotrochozoa, Deuterostomia. Canterbury University Press, Christchurch.

• 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