Chelae

A chela (/ˈkiːlə/) – also called a claw, nipper, or pincer – is a pincer-shaped organ at the end of certain limbs of some arthropods.

For instance, some species, such as the members of the families Ocypodidae and Alpheidae show asymmetry between their paired claws.

[5] An example of specialization of these asymmetrical chelae can be seen in the Alpheus heterochaelis, the bigclaw snapping shrimp.

The enlarged snapping claws of these shrimp are capable of snapping shut with such force to shoot a jet of water and create a loud popping noise, which they use to deter predators and other members of their species.

For scorpions, the chelae are formed at the end of the pedipalps and covered in sensory hairs that they use in a similar manner to insect antennae.