Upside-down jellyfish

Description:

They are found in warmer coastal regions around the world, including shallow mangrove swamps, mudflats, canals, and turtle grass flats in Florida, and the Caribbean. The medusa usually lives upside-down on the bottom, which has earned them the common name. Where found, there may be numerous individuals with varying shades of white, blue, green and brown.

Habitat:

In the past I have seen them in the Keys, FL while kayaking through mangroves. These live in the Aquarium of the Bay, SF.