Powell, A.W.B. 1979New Zealand Mollusca: Marine, Land and Freshwater Shells, Collins, Auckland (p.179)
Powell, A.W.B. 1952 New Zealand Molluscan Systematics with Descriptions of New Species: Part 1, Records of the Auckland Institute and Museum, 4(3) (p.179)
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 approximation of the range of each species within New Zealand.
K=
Kermadec Islands
A=
Aupourian - Kaipara Harbour, north around North Cape, encompassing the Three Kings Islands and south to East Cape
C=
Cookian - Lower North Island and the northern part of the South Island