Nanula tasmanica (Petterd, 1879)
Description: Shell width equal to height; aperture less than half total shell height. Whorls rounded, sculptured with fine spiral riblets, about 30 on the body whorl including base. Basal margin weakly angled in large shells. Aperture almost circular; outer lip simple, thickened internally in mature shells. Columella and aperture smooth. Umbilicus open, less than half covered by reflected lip of aperture. Colour variable; fawn, sometimes with white spiral bands at suture and periphery, or with irregular axial white streaks.
Size: Up to 5 mm high, 5 mm wide.
Distribution: Endemic to Australia; Iluka, NSW, to southern Tas.
Habitat: Taken in 10-130 m. Uncommon.
Remarks: Nanula galbina (Hedley & May, 1908) is very similar, and is probably only a form of this species. It is recognised from only a few specimens, with a range from southern NSW to South Australia.
Figs. 1,2: Frederick Henry Bay, Tasmania (C.010777)