etpisoni[1]) is a subspecies of spotted jellyfish (Mastigias papua) that inhabits Jellyfish Lake on Eil Malk island in Palau in the western Pacific Ocean.

[2] Like the nominate subspecies, it derives part of its nutrition from symbiotic algae (Zooxanthellae) that live in their tissues and part of their nutrition from captured zooplankton.

in the name) because the individuals local to Palauan lagoons may be only one of several cryptic species that make up the M. papua group.

[4] The subspecies carries out well-characterized daily migrations that are driven by light conditions in the lake.

This was apparently caused by a die-off of the symbiotic zooxanthellae due to increased water temperatures during an El Niño weather event.