Starfish in a sea urchin
Here are two small Upper Cretaceous sea urchins.These small, high-domed urchins are well-detailed, with the central mouth and the anus clearly visible in the specimen on the left.
The five radial sections are also very clear and reflect the common ancestry between sea urchins and starfish. These five radial sections are the equivalent of the five arms of a starfish, joined at the tip to form the shell or ‘test’.
