Blaklie Atkins- White Spotted Jellyfish By danasnyder820 Jul 1, 1981 The First White-Spotted Jellyfish Was Discovered On July 1, 1981 in Calafornia the White - Spotted - Jellyfish was first discovered by a scientist. May 29, 1993 Danger! On May 29, 1993 the White - Spotted - Jellyfish has been invadeing different areas of the United States, Japan, and in the Gulf of Mexico.