Real Monstrosities: Black Coral

Weird how it's a Black Coral yet it's the only thing that isn't black.

Black Corals, also known as Thorny Corals, are some 230 species in the Antipatharia order.

Image: hjk_888

Most live in deep, dark tropical and subtropical waters, but they can be found from pole to pole and surface to depth.

Image: kanuck

They come in a huge range of shape and colour...

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Some are extremely bushy, with lots and lots of branches...

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Others are just a single spiral, just like that American bank guy's signature...

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Still others don't even bother with a spiral. It's just a wobbly line!

Image: Nick Hobgood

These simple, unbranched Black Corals are often called Wire Corals or Whip Corals, just like simple, unbranched Gorgonians are. Whoops! But there are a couple differences to look out for.

Image: Nick Hobgood

One difference is revealed by a close look at the polyps.

Image: Lophelia II 2009: Deepwater Coral Expedition: Reefs, Rigs, and Wrecks, NOAA/OER

Each one is armed with an array of stinging tentacles for capturing prey which they share with the other polyps in the colony. But Gorgonians are Octocorals - each polyp has 8 tentacles. Black Corals are Hexacorallia - their polyps usually have 6 tentacles, though some have 12, 18 or 24.

Image: JohnWTurnbull

To see the other difference you'll have to get involved in some violence and gore. How could you?!

We've already seen that few of these so-called "Black Corals" are actually black. But what happens if you kill one and tear off its flesh with your teeth like a sick barbarian?

Image: DanPickedMinerals

You're left with its skeleton. A black skeleton! It's made of a tough protein simply called antipatharin and you can make all kinds of cool stuff out of it. It's even the state gem of Hawaii!