What is "calappa"

Calappa is either:

• Calappa (crab), a genus of crabs, including the box crab
• Calappa (palm), a genus of palm trees

Calappa is a genus of crabs known commonly as box crabs or shame-faced crabs. The name box crab comes from their distinctly bulky carapace, and the name shame-faced is from anthropomorphising the way the crab's chelae (claws) fold up and cover its face, as if it were hiding its face in shame.