Mediterranean violet sea urchin (Sphaerechinus granularis) on a gold sponge (Aplysina aerophoba).

Marino Linic

a group of sea urchins floating on top of a sandy bottom

Stefan Sebök

Three Mediterranean violet sea urchins (Sphaerechinus granularis) in three different color forms—red, white, and purple—on a gold sponge (Aplysina aerophoba).

a close up of a sea shell on a bed of blue rocks

Anne-Marie Allesø Rasmussen

A small orange object sitting on the ground

white and brown seashell on brown wooden table

Moon Moons

Keva Fawkes

a close up of rocks and gravel on a beach

Urchin