Tripneustes gratilla is a sea urchin from the class of Echinoidea and family of Toxopneustidae. It is commonly known as the Collector urchin or the Striped sea urchin. It has a round shape and is a dark bluish-purple colour with white or colourful short spines and tubular feet. Its body is called a corona or test and is divided into an oral and aboral surface. This species can reach up a diameter of up to 16 cm. It is called the urchin collector as it tends to gather debris on its spines and body.
The striped sea urchin is present across the Indo-Pacific regions, Hawaii, the Red Sea and the Bahamas. Its recorded depth range is between 2 to 30m but it has been recorded at 75m. It can be found in intertidal and subtidal regions, seagrass beds, coral reef areas, reef lagoons and rubble. Collector urchins are grazers and their diet consists of macroalgae, seagrass, and diatoms. When eggs hatch embryos undergo a planktonic phase before settling on the ground and metamorphosing into juveniles.
The conservation status of this species has not been evaluated yet. However, the population can be affected by overexploitation and local extinction in some areas.
Tripneustes gratilla is hunted by humans for its delicious gonads and is preyed upon by parrotfish, triggerfish, pufferfish and sea stars.