• Mellita quinquiesperforata
• Flat version of sea urchin
• Fused skeletal plate forms rigid exoskeleton (test)
• Lives in shallow water, using sand as protection
• Male and female cannot be distinguished by external features
• 5 petal pattern corresponds to Sea Star's 5 arms and 5 rows of tube feet
• Tiny moveable spines covering test used to burrow
• Tube feet extending from petals used for respiration
• Mouth contains Aristotle's Lantern (part that rattles when sand dollar dries)
• Feeds on detritus and plankton
• Predators include fish and turtles
