Scorpion Reef (Spanish: Arrecife Alacranes) is a reef surrounding a small group of islands in the Gulf of Mexico off the northern coast of the state of Yucatán, Mexico. Designated a national park, the reef is part of the Campeche Bank archipelago and is the largest reef in the southern Gulf of Mexico. Scorpion Reef contains the five main vegetated islands of Isla Pérez, Isla Desertora, Isla Pájaros, Isla Chica, and Isla Desterrada. Isla Perez is the only inhabited island and includes a lighthouse.