Violet Sea Urchin, Sphaerechinus granularis, Istria, Adriatic Sea, Croatia

sea urchin urchins echinoidea sting stinging toxic poison prick poisonous venomous aching painful prickles aculeate uni underwater marine wildlife marine fauna nature aquatic sea ocean underwaterphoto underwaterpicture underwaterphotography underwaterworld sealife adriatic sea mediterranean sea europe istria reef violet sea urchin sphaerechinus granularis istria adriatic sea croatia echinodes echinodeata horizontal foat