Big acorn barnacle shell, ~20x20x20mm.
On gastropod 35mm long, with the remains of a broken off second barnacle.
Outside looks like 4 large and 2 small white/light pink triangles, alternating with 6 medium pink inverted triangles. Not porous, not ribbed.
Officially has 6 plates, 2 large with wings, and 4 small. Lid (missing) pale pink.
ID key in Tuatara Vol 15 Issue 2:-
http://nzetc.victoria.ac.nz/tm/scholarly/tei-Bio15Tuat02-t1-body-d3.html#Bio15Tuat02-fig-Bio15Tuat02_079a
