The noble pen shell, Pinna nobilis, largest bivalve of the Mediterranean. They are highly endangered due to overexploitation and destruction of their native seagrass environment. They can grow up to a millimeter each day, making them some of the fastest growing bivalves in the world.
…a species of colonial porpitid hydrozoans which occur in tropical and sub-tropical waters of the Pacific, Atlantic, and Indian Oceans. Although blue buttons look similar to jellyfish they are actually a colony of numerous hydrozoan polyps. Blue buttons are typically seen drifting on the surface of the ocean where it feeds on zooplankton which drift too close. Blue button colonies consist of two main parts: the float which is a hard brown circle which keeps the colony afloat, and the colony which forms the “tentacles” of the organism, these tentacles are laced with nematocysts which are used to dispatch prey.