Details for crayfish identification involve seeing good, clear, CLOSE images of: the rostrum (nosepiece between eyes), areola (curved lines on the back), the chelae (claws, aka pincher laid flat), for best species ID one should have a male (best 1st form) and see the shape of an individual gonopod which is the 1st pleopod (swimmeret,paired between hindlegs) that is a sperm transfer device. Color pattern sometimes is useful. It helps to know the state and watershed where it was collected.

Some common Midwest crayfish:
https://pages.wustl.edu/mnh/crayfishes-prairie-region-missouri

Last edited by Bill Cody; 03/07/16 11:36 AM.
aka Pond Doctor & Dr. Perca Read Pond Boss Magazine -
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