These urchins are dark in colour, usually black, dark purple, or reddish brown, with white spines 1 to 2 cm long. They can reach 10 to 15 centimetres (3.9 to 5.9 in) in size. They are often covered with seagrass and debris similar to the closely related Tripneustes gratilla.
They are common in the Caribbean, Bahamas, and Florida, and may be found at depths of 0 to 10 metres (0 to 33 ft).
saw maybe 40ft down wile diving bonaire, it looks just like a ball covered in spikes.