Bill D., I think you are talking about Mantis Shrimp.

If you find any alive, don't pick them up unless you have armored gloves on.

http://video.nationalgeographic.com/video/worlds-deadliest/deadliest-mantis-shrimp

http://en.wikipedia.org/wiki/Mantis_shrimp

I caught one once near San Diego and was told not to pick it up or grab it or I could get speared. HUH? O.K. IIRC it was around 8"-9" long.

www.hoosierpondpros.com

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