Crab claw sail

The crab claw sail is a fore-and-aft triangular sail with spars along upper and lower edges. The crab claw sail was first developed by the Austronesian peoples by at least 2000 BCE. It is sometimes known as the Oceanic lateen or the Oceanic sprit, even though it is not restricted to Oceania, is neither a lateen sail nor a spritsail, and has an independent older origin.