Echinometra

Echinometra is a genus of sea urchins in the family Echinometridae, commonly found in tropical and subtropical marine environments worldwide. These small to medium-sized urchins typically measure between 2 to 7 centimeters in diameter and are characterized by their cylindrical shape and relatively short spines. The genus includes several species that are ecologically important in intertidal and shallow subtidal zones.

Members of Echinometra are known for their ability to bore into hard substrates such as coral rock and limestone, creating protective cavities where they reside. They possess specialized tube feet and a robust Aristotle's lantern structure that aids in this boring behavior. These urchins primarily feed on algae, playing a crucial role in controlling algal growth on coral reefs.

The genus exhibits significant morphological variation across different species, with some displaying distinctive color patterns and spine arrangements. Echinometra species are important prey items for various marine predators including fish, crustaceans, and birds. Their grazing activities contribute to reef health by preventing algal overgrowth that can otherwise outcompete corals for space and light.