Southern California’s increasingly tropical-looking ocean has delivered another stunner. A giant oceanic manta ray — the largest ray species on Earth — was filmed off San Diego by Net Zero Expeditions , an encounter the company says may represent the first documented sighting of the species in local waters. The species can grow 29 feet across, an enormous wingspan even for a animal known for reaching extraordinary size. The group published footage under the title “Endangered Oceanic Manta Filmed Off San Diego.” Check out the video below. The footage shows the manta gliding through blue water, its wing-like pectoral fins dwarfing the fish around it. Unlike stingrays, oceanic mantas are gentle filter feeders, consuming huge quantities of zooplankton. NOAA lists Mobula birostris as threatened under the Endangered Species Act and identifies it as the world’s largest ray.…