is the only group of decapods that doesn't have chelae, although females may have tiny chelae on their hind legs. Shrimps of the genus Psalidopus bearing an exceptional pair of scissor-like chelae that both fingers are mobile, with one of them possibly modified from an originally fixed finger.

Outside of decapods, other crustaceans known to have chelae are tanaids, some amphiopods, pennellid