G. atlanticus preys on other larger pelagic organisms: the dangerously venomous Portuguese Man o' War Physalia physalis... G. atlanticus is able to feed on P. physalis due to its immunity to the venomous nematocysts. The blue sea slug will consume the entire organism and appears to select and store the most venomous nematocysts for their own use. The venom is collected in specialized sacs (cnidosacs), on the tip of their cerata, the thin feather-like "fingers" on its body. Because Glaucus stores the venom, it can produce a more powerful and deadly sting than the Man o' War upon which it feeds.Which is why you shouldn't hold it on your hand for a photo...
More at the Sea Slug Forum. Via Reddit.
I'd always wondered how to pluralize Man-o'-war.
ReplyDeleteThere's great footage of a glaucus attacking one of the big colonial jellies in Life On Earth. I couldn't find it on Youtube, though I did find the piece of music written for that part of the series:
ReplyDeletehttp://waxidermy.com/audio/edward_williams_2.mp3
(just type in the code and you can play the mp3, no need to download)