Small, solid, mytiliform, with a tendency to spiral growth, rather inflated; dorsal posterior and ventral margins arched, anterior straight or concave; umbos terminal swollen, without visible protoconch; shell colour red or purple; externally smooth, coarse irregular concentric sculpture, no radials; hinge plate broad, widening posteriorly, projecting into one valve; chondrophore oblique, long, curved, separating two overlapping crenulated bands, one shorter, subumbonal, with fewer stronger lines; the other longer, posterior, with more numerous but weaker crenulations; no marginal teeth; margin smooth, except on the posterior side, where it is broken into five prominent, interlocking tubercles; both posterior and anterior adductor scars are visible; pallial line simple. Length 2.9 mm., height 3.8 mm., section 2.4 mm. Type locality: Eagle Hawk Neck, Tasmania, in shell sand.

Shell small, solid, mytiliform, with a tendency to spiral growth, rather inflated. Dorsal posterior and ventral margins arched, anterior straight or concave. Umbo terminal, swollen, without visible protoconch. Colour uniform red or purple. Externally smooth, coarse irregular concentric sculpture, no radii. Hinge-plate broad, widening posteriorly, projecting into the valve. Chondrophore oblique, long, curved, separating two overlapping crenulated bands, one shorter, subumbonal, with fewer stronger lines; the other longer, posterior, with more numerous but weaker crenulations. No marginal teeth. Margin smooth, except on the posterior side, where it is broken into five prominent, interlocking tubercles. Both posterior and anterior adductor scars are visible; the pallial line is apparently simple. Height 3,8 length 2,9; diameter of single valve 1,2 mm.

Hab. — Tasmania: Eagle Hawk Neck (type, in shell sand collected by Mrs. C. Hedley, 27th May, 1903); Ulverston, among kelp roots (Miss Lodder); Scamander Biver (Miss Lodder)—New South Wales : Long Bay near Sydney, in shell sand (M Parkes).