Chelidonura spp.
General Biological Notes

Superfamily: PHILINOIDEA
Family: Aglajidae

This page has general observations on chelidonurids. See the Chelidonura varians Page for further observations and discussion on feeding in Chelidonura.

Authorship details
Rudman, W.B., 1999 (June 19) Chelidonura spp. General Biological Notes. [In] Sea Slug Forum. Australian Museum, Sydney. Available from

Related messages

Chelidonura - feeding observations

June 19, 1999
From: Monica Sullivan

Dear Bill,
Here is a third bit of info I observed in SE Sulawesi, Indonesia, last year (Operation Wallacea )

I was having some ear trouble for a few days, so I couldn't dive but I managed to set up a small research project on chelidonurids, feeding, tides, etc. for a student. I took a lot of specimens up to the lab for binocular i.d.. It wasn't until I had a petri dish full of them under the microscope that I saw one of the chelidonurids follow the exact trail of a flatworm, until it caught up with it. I watched it with great excitement as what can only be described as it 'unzipped' the worm and sucked out its interior. It did not kill the worm, but instead allowed it to crawl off. Are you familiar with this behaviour?

Monica Sullivan

Sullivan, M., 1999 (Jun 19) Chelidonura - feeding observations. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from

Dear Monica,
Any idea of the identity of the chelidonurid? and could you give us some indication of size?

I have been trying to find what chelidonurids fed on for years and it was only some messages last year on aquariists wanting Chelidonura varians to eat infestations of red flatworms that finally provided an answer to its food. The prominent sensory bristles on either side of the mouth suggest they track their prey so your observation of them following the trail is intersting confirmation. (See the pages on Chelidonura hirundinina and Chelidonura inornata for pictures of the sensory bristles).

I'm not sure I understand how they suck the flatworm's organs out and leave the skin as they have no biting organs, relying completely on suction to injest their prey. Perhaps they sucked out a recent flatworm meal?

Very interesting,
Bill Rudman.

Rudman, W.B., 1999 (Jun 19). Comment on Chelidonura - feeding observations by Monica Sullivan. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from