Jellyfish Lake, Eil Malk Island, Palau, Pacific Ocean

Two species of scyphozoan jellyfish live in Jellyfish Lake, moon jellyfish (Aurelia sp.) and the golden jellyfish (Mastigias sp.).
• Golden jellyfish
The golden jellyfish are most closely related to the spotted jellyfish (Mastigias papua) that inhabit the nearby lagoons. They are similar to the spotted jellyfish in that they derive part of their nutrition from symbiotic algae (Zooxanthellae) that live in their tissues and part of their nutrition from captured zooplankton.
However, the golden jellyfish are morphologically, physiologically, and behaviourally distinct from the spotted jellyfish. They are easily distinguished from the spotted jellyfish by the almost complete loss of spots on the exumbrella and the almost complete loss of their clubs, an appendage attached to the oral arms.