Unusual worm-like creature at Phil Foster Park

My buddies and I were diving at Phil Foster Park on Friday when my buddy spotted this unusual worm-like creature. She and I have each been diving at the park hundreds of times and we've never seen anything like this. It had undulating movements and was about 8" in length when it was contracted and about 14" in length when it was stretched.

Here's a few pics. Can someone please help to ID this? Thanks in advance! Robyn

It's in the phylum Echiura - spoon worms. The blueish gray part is its so-called proboscis with which it gathers food, mostly microbial and microscopic stuff associated with sediment, which it transports along the hollow, spoon-like part of its proboscis - as you see in the third pic. I've collected other worms in that area for many years and never seen this.

Nice pics! If you don't get an ID here and want one, try contacting folks at Smithsonian Marine Station in Fort Pierce, or John Pilger at Agnes Scott College.

As usual Jon is right as is his advice if you want a more exact id. There aren't many echiuroids reported from Florida - the SMS/Fort Pierce invert list doesn't even include them. I found mention of 3 species in the genera Lissomyema, Thalassema, and Ochetostoma. Of the 3, your critter best fits Ochetostoma because of the very distinct "grid" which is faint or not visible externally in the other two.

Thank you so much Leslie and Jon! Robyn