It is unclear whence M. stellata has arrived; yet, the native range of nine out of ten alien species recorded off the Israeli coast is the Indo-Pacific Ocean, the Indian Ocean or the Red Sea (Galil 2007), and one could argue that the Indo-Pacific is a hot-spot for cepheids.
Galil, B.S.; Gershwin, L.-A.; Douek, J.; Rinkevich, B. (2010). Marivagia stellata gen. et sp. nov. (Scyphozoa: Rhizostomeae: Cepheidae), another alien jellyfish from the Mediterranean coast of Israel. Aquatic Invasions 5(4): 331–340.