”This is my favorite photo in the world - me and Linus, born to a dairy cow and ordered to be killed when the farmer saw he was a male (and thus useless in the dairy industry). A compassionate individual intervened, and he was brought to a sanctuary. I met him when he was a few days old and 60 pounds, and he would always try to sit on my lap. Today, 7 years young and 1500 pounds, he still tries to sit on my lap.”
Also known as sea swallow, blue sea slug, blue angel or blue dragon, it is a small sized sea slug that lives in the Atlantic, Indian and Pacific ocean.
They feed mainly on other sea creatures like the Portuguese Man-o-War, a cnidarian often mistaken for a jellyfish. The Glaucus is immune to their venom, and can actually store it in its cerata ( their dorsal and lateral outgrowths on the upper surfaces of the body). As a result they can sting potential predators. The sting is quite painful for humans, so they should be handled carefully. At times, and given the occasion, they can be cannibalistic.
With the aid of a gas-filled sac in its stomach, the Glaucus floats at the surface. Due to the location of the gas sac, the sea swallow floats upside down.
Like almost all heterobranchs, Glaucus is a hermaphrodite, having both male and female reproductive organs. After mating, both animals produce egg strings.