BIOL 1503 Chapter : CrawfishDissection2011
Document Summary
They include arachnids, like spiders, scorpions, ticks, mites, insects, and the group we"ll look at in the lab - the crustaceans, which are mostly mostly aquatic. Crayfish are common freshwater crustaceans, related to lobsters, crabs, and shrimp. They are bottom dwellers and live as predators and scavengers. They live in small hollows or burrows that they back into, with their chelipeds, or claws, facing out. Get your dissection equipment, including a dissection pan, and a preserved crayfish. There should be a sheet with labeled drawings to help you identify the structures. Look closely at them - what similarities support this idea: the cheliped, of course, is not a walking leg - it"s adapted for defense and for grabbing prey. Inspect the swimmerets - they are the fine, leglike (they are supposed to be adapted legs) structures under the abdomen, behind the walking legs.
