Blue Lion’s Mane Jelly
From Openwaterpedia
noun - Blue Lion’s Mane Jellyfish (Cyanea lamarckii) is typically white to pale yellow. As they grow, they develop more of a color, which can range from grey to blue to purple. They use their up to 800 stinging tentacles to capture phytoplankton, zooplankton, and even other jellyfish to feed on and also for protection from predators. The bell of the blue lion’s mane jelly can grow to nearly twelve inches in diameter. They have oral arms that can reach the same length as their diameter. They are regularly observed in coastal waters off the British Isles.