Cucumber?

I am going through some pictures from last month and am having trouble getting and ID on this. Do all cucumbers have filter feeding tentacles? This guy is about 4 feet long and was about 25 feet down. It was also eating, with some gusto, the coral to the left.

That should be in your guide books as Bohadschia graffei (or graeffei) although the genus has been recently changed to Pearsonothuria. I love those flattened flower-like feeding tentacles. The idea that it would be eating coral would be news to any holothuroid specialist. It's a living mop, using its tentacles to pick up organic bits from soft & hard surfaces.

I've linked to three images. The first two show it feeding. The third shows an interesting bit of life history. Juvenile P. graffei look just like a species of nudibranch called Phyllidia varicosa which is extremely toxic. The baby cukes are defenseless but no predator would want to sample a phyllidid nudi.

http://perso.orange.fr/sulawesi.biologie.s...eviewpage8.html

http://www.underwaterpicture.com/cpg/album...raeffei%20k.jpg

http://www.seaslugforum.net/display.cfm?id=9380

I believe all cukes do have feeding tentacles.

Could it have been not eating but sweeping the coral looking for food? In the time I spent watching, it also lifted the entire front half of its body off of the seafloor and swayed back and forth. Made for a great picture of my wife who swam on the other side of it from me for a photo.

Sweeping is the right word as people consider the benthic feeders to be living vacuum cleaners!

By an interesting coincidence, I was "processing" my photographs from my GBR/Coral Sea trip in May on the weekend and I have this shot:

which I also IDed as B. graeffei.

Yup, just mopping up....