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Upside-down Jellyfish

Cassiopea xamachana


Photo take at the marina at 4 ft of water this jellyfish are very common on this area usually easy to find in very shallow waters is about 25 cm diameter whit this blue-purple tentacles. Cassiopea is a large jellyfish (up to about 30 cm in diameter) that is brown or olive and creamy white in color. Its underside is covered with extensions (oral arms) that branch into thousands of lacy extensions (lappets). These lappets contain thousands of photosynthetic yellow-brown zooxanthellae (mutualistic photosynthetic dinoflagellate algae). The lower margin of the bell is surrounded by multibranched tentacles. Cassiopea swims in the typical jellyfish orientation, with its mouth facing downward. However, unlike most jellyfish, Cassiopea is seldom seen swimming, instead spending much of its time flipped upside down, pulsating, on sandy or muddy substrates in mangrove or soft bottom bay habitats. This orientation provides its photosynthetic zooxanthellae with critical access to light.


Found ion shallow waters in estuaries and lagoons and mangrove areas on the Caribbean Sea and Gulf of México.

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Gerardo Aizpuru
Gerardo Aizpuru 8 years ago

Thanks Cecilia :)
I just add a small video!

Gerardo Aizpuru
Gerardo Aizpuru 8 years ago

Thanks Scott:)

ScottHarte 8 years ago

lovely find, great series

Gerardo Aizpuru
Gerardo Aizpuru 8 years ago

Thanks Cindy this is a beauty and is so common people are very scare of it but is harmless. you should try scuba some day:):)

Wow! What a spotting. Great series. I wish I knew how to scuba!

Gerardo Aizpuru
Spotted by
Gerardo Aizpuru


Spotted on Jun 29, 2012
Submitted on Jun 29, 2012

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