Thysanostoma loriferum (Rhizostomeae - Thysanostomatidae) is an oceanic species of scyphomedusa recorded from Philippines, the Malay archipelago, Hawaii, and the Red Sea, which is rarely seen inshore.
These animals have large narrow lash-like frilled mouth arms. The upper parts of the mouth-arms are very short and partially fused to the arm disk by a series of arches reaching from one to the next. The bells can be from 90 to 120 mm wide and the eight mouth arms are from one and a half to three times as long as the bell is wide. The lower arms are three winged and Y or T shaped in cross section through its length.
What is fascinating about the jellyfish is that at different stages of its life, its appearance tends to change quite dramatically. When the jellyfish are extremely young, the bell of the purple jellyfish is pinkish in color and does not have the dramatic stripes that characterize the adults. The tentacles of the very young purple jellyfish are long and dark and have a dark maroon color. As the purple jellyfish grows older and becomes a young adult, develop long, frilly oral arms that can look very impressive. These oral arms can attain the sixe of 4 to 5 meters in length. As the purple jellyfish matures into a full grown adult, the purple stripes appear along the bell and the color of the tentacles starts to diminish until they are almost colorless. As the jellyfish grow older, the tentacles become thick and pale and the oral arms of the jellyfish disappear.