Description:
Adult medusae of the hitch-hiking jellyfish are dime-sized in diameter. The hemispherical bell, with 4 radial canals, supports 4- 8 tentacles under the bell, and 16 to 128 hollow tentacles which surround the margins of the bell.  Stinging cells called nematocysts, used to immobilize prey or deter predation, are scattered along tentacles.   The marginal tentacles, containing gravity detecting statocysts at the base, can be extended for 1 or more inches.

Habitat:
Most collection of the hitch-hiking jellyfish has been done inadvertently.  However, it is found in association with algae such as Ulva, Sargassum, and Enteromorpha;  and in empty mollusk shells.

Range:
Hitch-hiking jellyfish have been described from southern Brazil to the Indian River Lagoon, where it was noted for the first time in 1990.