Is that pier on Howard Park Causeway? Trying to picture in my mind a pier, because I looked, well not hard but looked from public pier on river. I never did and only crabbed from pier in safety harbor, had better luck fishing than crabbing

Fungus on crabs ?

you meant like a moss or fuzzy like moss? If that is case that crab has just been hanging around not moving much since food for it must be plentiful. But anyway....better luck next time, oh and why crab so late at night? tides?