Long shot - long blueish creature at 100' in Saba

Unfortunately no one on the dive got a picture so I'll try to describe as best I can.

Saw a blueish-purple creature at 102' (31m) at Saba's pinnacles (90' / 27m at top, 200' / 60m plus at bottom) in the Caribbean. At first I thought it was a strange-colored sponge in a crevice, and on further investigation saw that it was moving, slowly. It was tubular, maybe 1.5" diameter, moving from one crevice to another so never saw the whole thing at once. I may have seen a head, but can't really be sure. It moved almost like a sea cucumber, oozing down from the higher crevice. For lack of a better description (sorry for the weak-stomached!) it looked like small intestines moving over the reef, but definitely blueish. We made sure to shine a light on it to counteract any underwater illusions. No markings on the skin, smooth texture, no dimples, not segmented, just some light transverse striations, again like some sea cucumbers. But I swear it was blueish purple...

Two Divemasters and three seasoned divers - all with a couple thousand Caribbean dives each! - had no clue what it was... Has anyone seen anything like this before?

Thanks for any help you might be able to provide! I'm insanely curious about this thing...


Design by Joanne Kidd, development by Ben Weintraub