Anisodonta (Tahunanuia) alata trigonia (Powell, 1952) Width 4.8mm, Height 3.5mm, Marine, Endemic. Shorter and more trigonal than alata and has the umbonal-ventral ridge stronger and distinctly angulate Off Campbell Island AnE.
Isoconcha integra (Hedley, 1907) Width 6mm, Height 3.5mm, Marine Southern North Island, South Island and Chatham Rise. Also South Australia to New South Wales. Commensal, attached to the external surface of the holothurian Mesothuria lacteaCFM
Key to Geographical Ranges
The symbols K.A.C.F.M.An. are used to indicate the geographical range of the species.
They have been adopted to give an approxomation of the range of each species within New Zealand.
Aupourian - Kaipara Harbour, north around North Cape, encompassing the Three Kings Islands and south to East Cape
Cookian - Lower North Island and the northern part of the South Island