Echinometridae

Echinometridae is a family of sea urchins, belonging to the class Echinoidea. They are characterized by their unique, elongated spines and a distinctive body shape. The family includes several genera, with the most well-known being Echinometra, which is commonly found in the Indo-Pacific region. Echinometridae are typically found in shallow waters, often in rocky or coral reef environments.

These sea urchins are known for their defensive mechanisms, which include the ability to expel their internal organs through their anus as a deterrent to predators. This process, known as evisceration, is a survival strategy that allows the urchin to escape from potential threats. The expelled organs can regenerate, making this a viable defense mechanism.

Echinometridae play a significant role in their ecosystems by contributing to the breakdown of organic matter and by serving as a food source for various marine organisms. Their unique biology and ecological importance make them a subject of interest for marine biologists and conservationists.