Box jellyfish box-like bell, from which its name is derived. From each of the four lower corners of this hangs a short pedalium or stalk which bears one or more long, slender, hollow tentacles. The rim of the bell is folded inwards to form a shelf known as a velarium which restricts the bell's aperture and creates a powerful jet when the bell pulsates. As a result, box jellyfish can move more rapidly than other jellyfish; speeds of up to per minute have been recorded. In the center of the underside of the bell is a mobile appendage called the manubrium which
Jellyfish Lake on Koror. The golden jellyfish population in Big Jellyfish Lake, Koror did not seem to be affected. The reason for this was not clear, but Big Jellyfish Lake experienced lower temperature increases than the other lakes and there was experimental evidence that the golden jellyfish medusa from Big Jellyfish Lake were more tolerant of higher temperatures. Although Clear Lake did not seem to have experienced the complete medusa population die-off that Jellyfish Lake did in 1998, the golden jellyfish medusae in Clear Lake are not always present. When conditions are not favorable for the short lived medusa stage or for