sea urchin on stone underwater and fish swimming

sea urchin stone underwater fish swimming venomous ocean mexico mexican spined life barrier reef spine natural wildlife tropical marine exotic nature aquarium coral indopacific animal setosum echinoidea great red urchins diadematoida waters diadematidae long pacific wild one water fauna longspined biodiversity environment weights bubbles oxygen depth poisonous latin america ston depp swiming perched rock where some swim