Phenacovolva wakayamaensis has had a name change, It is now called Kurodavolva wakayamaensis
see:
http://www.marinespecies.org/aphia.php?p=taxdetails&id=431185

I see that Phenacovolva wakayamaensis is listed in Nature Watch but with no details so thought I would report the spindle cowries (Phenacovolva wakayamaensis) that I collected off a deep reef (35m) just out side Tutukaka entrance in the 1980’s. They are very hard to spot underwater as the shell is covered by a white mantle that is covered with pink dots, the same colour as the pink slender branches of the Primnoeides gorgonian on which they feed. They are also found at the Poor Knights Islands and I have heard of them been found on deep reefs off Cape Karikari.
Their type locality is Balicasag Is. in the Philippines,

Young juvenile N. comptoni or N. piperita?

The mantle of comptoni is orange, and the mantle of piperita is pale yellow-grey or yellow. I don't know if the colour of the juvenile mantle is the same as the adult.

Currently, there are examples of juvenile cowry shells on iNat which appear identical in features, but have been identified on separate pages as 2 different species.

Hope this is the correct taxa, ID based mainly on the bubble raft formed by this species however the form of the shell does differ from other photos, this individual seems to be lacking a few whorls at the apex? found along with other members of the blue fleet, left on the beach with the incoming tide, wind had been NW onshore for at least 24 hours prior.

Found with several over members of the blue fleet, mid-incoming tide, NW onshore wind, washed up with the drift-line. To give a bit of context to the photos, I ended up with a hand full of Rams horn shells that had Fiona along with the Lepas. barnacles, these were placed in a plastic container with seawater to get some pics showing Fiona with cerata suspended.