horseshoe crab in the mud

alone animal anthropod arachnid atlantic bait book brown bulkheads camouflage chelicerata chinese coastal compound crab creature crustacean endoskeleton eyes fertilizer fish fishing fossil gills harvest horseshoe invertebrate isolated japanese lateral limulidae living mangrove marine molt mud natural nature ocean one ordovician roe sand shallow shore spawn strange strata tetrodotoxin trispine water weird wildlife