Jelly-Riding Crab Photograph by Hannah Johnson. A crab clings to its floating host as both are swept out to sea near Wrightsville Beach, North Carolina. One role jellyfish play in the marine ecosystem is the transport of other animals across the ocean.
Stone fish (Synanceia horrida) is considered the most venomous fish in the world. It looks like a stone. Its dorsal fins are lined with 13 spines that release venom from two sacs attached to each spine.