Ilbia ilbi from Victoria

December 26, 2000
From: John Chuk

Dear Bill,

I seek help in identifying two species of cephalaspideans I photographed in Port Campbell Harbour, here in Victoria, [Australia] in February 1999. Views of both specimens are attached. Unfortunately these are not great photographs as all specimens were 4mm in length and fine detail is lacking.

The first species is a dark purple colour with white patches and yellow lines and spots. The cephalic shield appears joined to the mantle and parapodia are lacking. No gills were visible. Only one specimen was sighted and it was found on an algal stipe in 3m of water. It may be Ilbia ilbi but I'm not at all sure.

Any help in identifying this animal would be gratefully appreciated!
John Chuk

Chuk, J., 2000 (Dec 26) Ilbia ilbi from Victoria. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from

Dear John,
Your animal is Ilbi ilbi, one of two quite common runcinids from southeastern Australia. They are seldom noticed however because they are so small.

In case you are wondering what happened to your other photo, I have separated it into a separate message. Just as a general comment to everyone, if you have questions on more than one species it helps me a lot if you send them as separate messages, even if it means repeating collecting data etc. I try and link messages and photos to a relevant species page so if you send combined messages I have to then untangle them into separate messages.

Hope you are having a restful Christmas holiday,
Best wishes,
Bill Rudman.

Rudman, W.B., 2000 (Dec 26). Comment on Ilbia ilbi from Victoria by John Chuk. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from


Ilbia ilbi