Oblong Sea Urchin

Echinometra oblonga shows a range of color from dark purple to black. Their spines are shorter, and more blunt than other species of Echinometra.

Echinometra oblonga generally live in rougher-water areas of tropical reefs. To protect themselves from the force of the waves, they live in the holes of the reef, but they also live on exposed reef flats. As the urchin grows, they use their jaws to help enlarge holes in the reef. Their spines trap seaweed and algae from the reef, which they then transfer to the mouth.

Echinometra oblonga, are gonochoric. They fertilize externally. Their eggs are either held on the peristome or around the periproct.