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Velella - Sail-by-the-wind

Velella velella


These small cnidarians are part of a specialised ocean surface community that also includes the cnidarian siphonophore known as the Portuguese Man o' War, as well as some specialized predatory gastropod mollusks, including nudibranchs (sea slugs) in the genus Glaucus and purple snails in the genus Janthina, all of which eat Velella. Each Velella is a hydroid colony, and most are less than about 7 cm long. They are usually deep blue in colour, but their most obvious feature is a small stiff sail that catches the wind and propels them over the surface of the sea. Under certain wind conditions, they can become stranded on beaches in the thousands. In common with other Cnidaria, Velella are carnivorous animals. They catch their prey, generally plankton, by means of cnidocyst (also called nematocyst) -laden tentacles that hang down in the water. Though the toxins in their nematocysts are effective against their prey, Velella are harmless to humans, either because their nematocysts are unable to pierce our skin, or perhaps because humans do not react to the toxins encapsulated in their nematocysts. Nevertheless, it is probably wise not to touch your face or eyes if you have been handling Velella.


Bear Cut, Virginia Key, South Florida Peninsula

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Jacob Gorneau
Jacob Gorneau 7 years ago


Leuba Ridgway
Leuba Ridgway 8 years ago

just came across this spotting - what a beauty ! I've found hundreds of dried-up floats with sails but no live animals and definitely no colour at all....thanks for sharing this.
Our waters are too cold !

ChunXingWong 8 years ago

I have never seen anything like this in my life !
Well done for sharing such a unique creature.

KarenL 8 years ago

Very interesting! I've moved this to Others for you.

AntónioGinjaGinja 8 years ago

beautiful,great spotting,congratulations

Ava T-B
Ava T-B 8 years ago

This is amazing and beautiful; can you add any information about this species? Or perhaps a reference about it?

BrandonBlount 8 years ago

That is so neat! I have never heard of such a thing! Fantastic Spotting!

MelissaFerguson 8 years ago

I have never seen one of these...great find and photos! Thank yo for posting in Florida's Flora & Fauna mission!

Spotted by

Miami, Florida, USA

Spotted on Apr 11, 2010
Submitted on May 18, 2012

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