This was observed at night in the Tulamben area. Instead of a sponge, the crab was carrying the nudibranch Jorunna funebris. Whenever the crab would stop moving, the slower nudibranch would try to twist around and grab the substrate, but the crab was moving too often for him to get a good grip and escape. It is probably the same as the other one we are calling Dromidiopsis cf australiensis.
Created 18 September 2021