halcyon's picture

Unidentified creature

Observed: 28th August 2007 By: halcyon

I came across a few of these strange looking things washed onto the shore on a Brittany coastline, back in 2007. I've always wondered what they might be.
They are quite large - probably between 8 - 10 inches long, and have semi-transparent skin in some parts. As you can see in the pictures, they have a shiny dark rounded point at one end and are fatter at the other end, with a protruding part. There is a dark textured covering over part of them.
They're very alien looking and were quite disturbing to come across!

Species interactions

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ChrisMcA's picture

This is totally mysterious &

This is totally mysterious & intiguing; is this 2 shots of the same individual?

halcyon's picture

No, we came across two or

No, we came across two or three of them, but they were all similar. This shows two different ones, but if you turned the first one over it would have looked like the one shown in the second image.

Nick Upton's picture

Very intriguing...

I've been trying to work out what these could be and have no definite answers. They look molluscan to me - like some aberrant form of sea slug. Just possible a side-gilled seaslug (Notaspidea) as they can be big, do get stranded on occasions and have some features that match your pics. Most images online are of live animals underwater and their shape changes a lot when exposed, so many look nothing like yours and I can't find a really convincing match, but this gets somewhere near: http://picasaweb.google.com/lh/photo/B7bRWzOJ6U7KZDesz7D8aA

Maybe worth posting this in the invertebrates section as more people might see it and chip in.

Nick Upton, naturalist and photographer.

halcyon's picture

Thanks Nick, I'll try posting

Thanks Nick, I'll try posting it in Invertebrates.

ChrisMcA's picture

Pleur. membr.

Have you any photos or illustrations of P.m. in mind, Gramandy? I wondered if they might be the soft parts of a large shell like a conch, removed so as to sell the shells

ChrisMcA's picture


This post has been reposted in invertebrates at http://www.ispot.org.uk/node/295772 Gramandy, & nick's reposted an amended response there, so it'd be better to repost comments there & then shut this down. But I noticed in MarLIN's P.m., http://www.marlin.ac.uk/speciesinformation.php?speciesID=4142 the external lung is very small

dejayM's picture

ha'penny's worth

Whilst the other post is now shown in the >>Marines Project<< I thought I'd add my ha'pence (not worth much).