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Do dragons exist?


crandf
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http://www.seaslugforum.net/factsheet.cfm?base=glauatla

Anyone has it in their tanks?

Glaucus atlanticus

Forster, 1777

Order: NUDIBRANCHIA

Suborder: AEOLIDINA

Family: Glaucidae

DISTRIBUTION

Circumglobal in temperate and tropical waters.

Glaucus atlanticus and its close relative, Glaucilla marginata, live in close association with what Sir Alistair Hardy described many years ago as "The Blue Fleet" - the siphonophores such as Physalia, Velella, Porpita and the other associated animals including the "Violet snails" of the genus Janthina. All these animals float on the surface of the ocean being carried by the currents and the winds. Most of us are only aware of their existence when days of onshore winds blow great fleets of them on to the beaches, causing pain and angst for swimmers.

Both species spend their life floating upside down in the water, partially bouyed by a gas bubble in their stomachs.

The two nudibranchs feed almost exclusively on Physalia, and as Tom Thompson and Isobel Bennett reported some years ago, it appears that they are able to select the most venomous of Physalia's stinging nematocysts for their own use. Like most aeolids, they store the nematocysts in special sacs (cnidosacs) at the tip of their cerata .

There are a number of reports in Australia of kids engaged in "Bluebottle" fights - where they throw stranded Physalia at each other - being badly stung by inadvertently playing with Glaucus and Glaucilla, both of which, by concentrating the most venomous of Physalia's nematocysts, are much more deadly.

Another interesting feature of the two species is their colouration. They both exhibit a textbook example of colour countershading. Their foot and undersides of the cerata, (which because they float upside down is effectively their dorsal surface), is blue or blue and white which helps to camouflage them from predation (sea birds) from above. Their true dorsal surface, which faces down in the water, is silvery grey to effectively camouflage them from fish looking up from below.

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Saw it on Discovery channel a few months back. Eat feeds on Jellys if im not wrong and its NOT reef safe :lol: :lol: :lol:

Reefing since 2003
 4ft x 2ft x 2ft Mixed Reef (BB):-
50 Gal Sump,

Apex Controlled System (Lab grade),
Deltec SC1455 Protein Skimmer,
Vortech MP40wQD,

Jebao RW-15

Maxspect Razor 320w
Eheim 1260 Return Pump,
Hailea HS-66A 1/4HP chiller,
TLF Reactor 150, running HydroCarbon 



 

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