The solution to Bit-o-Critter round 22

Well I really have to hand it to juliebug.  I was sure I would have stumped you guys on that last one, but no!  Julie nailed it - it was a sea pig, a bizarre deep sea holothurian, a sort of sea cucumber.  These pallid little blobs inch their way across the abyssal depths, eking out an existence on the snow of detritus raining gently down from above.  Great job Julie, truly impressive.