astronomy-to-zoology: Blue Button (Porpita porpita) …a species of colonial porpitid hydrozoan
astronomy-to-zoology: Blue Button (Porpita porpita) …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. Classification Animalia-Cnidaria-Medusozoa-Hydrozoa-Anthomedusae-Porpitidae-Porpita-P. porpita Images: Bruce Moravchik and Tanay PrabhuDesai -- source link