black sea, hydroids obelia, (coelenterates), macrophytes red and green algae

algae macrophytes coelenterates hydroid obelia animal aqua black sea cnidaria colonies crash destroyed dive ecological environment fauna hydrozoa invertebrate jelly jellyfish lange zeedraad laomedea longissima life marine medusa nature flabellata plana polyp reproduction water undersea underwater wild wildlife wreck wreckage