The egg yolk jelly, sometimes called the fried egg jelly and, less intriguingly but more scientifically, Phacellophora camtschatica, has a delicate milky white bell with prominent golden yellow sex organs massed in the center. The short, folded oral arms look a little like broken yolk running from the bell. Its threadlike tentacles, grouped in 16 clusters, are white and amazingly long—up to 20 feet on a jelly with a 2-foot-diameter bell. They’re also sticky, the better to collect zooplankton and smaller jellies, including moons, to eat. At Shedd, we raise tiny shrimp and other planktonic animals for the jellies. They also eat “Cyclop-eeze,” a commercial frozen planktonic food.
It’s easy to get scrambled up telling apart the egg yolk jellies and the also-yellow lion’s mane jellies. But your jellies field guide would point out that the former have 16-lobed bells compared to the latter’s eight lobes. The lion’s manes also have a bit more brown or red in them.
Like eggs, these jellies are fragile. They pulse lightly or not at all, simply drifting motionless on currents. Waves can distort or invert the diaphanous bell. And those long, long tentacles can get tangled among several jellies, so that they look like eggs sitting in ultrafine angel hair pasta. Mark Schick, special exhibit collection manager, says that the jellies usually unknot themselves in a couple of hours. If that doesn’t happen, he can use a thin glass rod, known in the profession as a “tickle stick,” to tease apart the tentacles. “Or we can just use our hands to separate them without damage,” he says. The absence of damage extends to the aquarists, too—egg yolks have only a mild sting.
Posted by Karen Furnweger, web editor