January 25, 1999
From: Bernard Picton
I was having a good read through the forum over Christmas, it's really going well!
I enclose two pictures of Philine aperta, as you have a page for this species but no photos. I note that this species lives on soft mud, into which it presumably can burrow, yet normally it is seen moving across the surface leaving a trail. I suspect that some gastropods which feed on bivalves may move at the surface until they encounter a bivalve siphon, then burrow down after it. The prosobranch Natica (now Euspira) seems to do the same thing in my experience. In a big animal like this (3-4 cm) I imagine moving through the sediment would consume considerable energy?
I've copied the message to Chris Duffy, who asked about P. aperta in an earlier message.
We also have observations of Stiliger bellulus(?=Calliopoea oophagus) feeding on the eggs of Philine aperta.
email@example.comPicton, B., 1999 (Jan 25) Photos and observations on Philine aperta. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/513
Thanks for the pictures and information. I have watched the very similar Philine angasi burrowing in New Zealand and it reminds me very much of the way the foot of a tellinid bivalve burrows into quite hard impacted sand. The front of the head narrows and thins, wiggling its way between the sand grains before forcing blood forwards to enlarge the hole through hydrostatic pressure. Your mention of naticids reminds me of watching a remarkable Philine-like naticid, probably Sinum? or Ectosinum? in Tanzania, which burrows much the same way. Naticids can apparently take up water to expand the size of their foot when burrowing, though how they do this doesn't seem very clear.
If you have any photos of Stiliger bellulus to spare they would be an interesting addition to the Forum.
Philine aperta from east of Cape Town
From: Eddie Hardy, December 23, 2004
Philine aperta from Tunisia
From: J. Ben Souissi and A. Eters, July 26, 2003
Philine aperta? from Mediterranean France
From: Erwin Koehler, December 17, 2001
From: C. Duffy, October 9, 1998