Common name: Upside-down jellyfish

General information

The Upside-down Jellyfish, scientifically known as Cassiopea xamachana, is a unique species of jellyfish that is popular among marine enthusiasts for its peculiar habit of resting bell-upward on the substrate. This behavior allows the symbiotic algae, called zooxanthellae, living in its tissues to photosynthesize, providing the jellyfish with nutrients. The Cassiopea Jellyfish is also known for its mild sting, which can cause irritation in humans.

Care

Caring for Upside-down Jellyfish in captivity requires a specialized setup to mimic their natural environment. They thrive in shallow, warm, and calm waters with plenty of sunlight to facilitate the photosynthesis of their symbiotic algae. A sandy bottom is essential for them to rest upon, and the water quality must be maintained at high standards to prevent infections and promote health.

Reproduction

Upside-down Jellyfish reproduce both sexually and asexually. In sexual reproduction, they release sperm and eggs into the water column, which develop into free-swimming larvae. Asexually, they can produce tiny clones of themselves through a process called budding, where new jellyfish grow directly from the adult's body.

Symbiosis

The most notable symbiotic relationship of the Upside-down Jellyfish is with the zooxanthellae algae. These algae reside within the tissues of the jellyfish and perform photosynthesis, providing the jellyfish with oxygen and organic compounds. In return, the jellyfish offers the algae protection and exposure to sunlight.

Habitat

Naturally found in warm coastal regions, including mangrove swamps, mudflats, and shallow lagoons, the Upside-down Jellyfish is often associated with still or slow-moving waters. They are commonly seen in the Caribbean Sea, Gulf of Mexico, and along the coast of Florida.