White "critter" attached to barrel sponge, Phuket, Thailand

[huskychemist]

Any idea what the white thing attached to this barrel sponge might be?

I took this picture at Koh Bida Nok near Koh Phi Phi. It was probably 10-15 msw. I've seen alabaster sea cucumbers on barrel sponges in the Gulf of Thailand before, but I've never seen anything like this.

Any thoughts?

Many thanks!

 

[Diver Dennis]

They are some type of worms. They have tentacles coming out of the...er, front end... We have lots here in the Philippines as well.

 

[LeslieH]

Hi Lowell -- It's also a sea cucumber. Either the feeding tentacles are retracted into the body or they're otherwise out of sight. If you do an image search for Euapta, Opheodosoma, or Synaptula you'll find pictures of similar animals.

 

[huskychemist]

Hi Leslie,

Thanks. I'll do a little looking. I wasn't sure, as the body type is a bit odd to me, given the "segments" it seems to have, but I didn't see any feeding tentacles to help figure out what it was. I only snapped the one picture, so I don't have any other pictures to look for the tentacles.

I've seen the "alabaster sea cucumber" which, to the best of my knowledge, is in the genus Synaptula also. (Although I understand the trouble with common names...)

Thanks.

Lowell

 

[LeslieH]

You can see why the common name for these is beaded sea cucumbers.

 

[huskychemist]

Hi Leslie,

The closest of the "beaded sea cucumbers" seems to be Euapta godeffroyi.


Deep Sea Images Library - Head of a Beaded Sea Cucumber - Euapta godeffroyi - Natural History Images


The E. lappa seemed to have color patterns that didn't match my critter.


Thanks again.

Lowell