The Button Coral

Anemones and Corals often have shared traits.  Anemones contain algae which convert light energy into chemical energy.  Thus a sun-lit anemone can survive for long periods of time without "eating" solid food because it consumes some of the sugars which the algaes produce.

The Button Coral is similar in many respects. It, too, has algae which it uses to convert light energy into chemical energy.  At night, when there is no light, it collapses into a small cylinder perhaps 1.5" across and 2 " high.  When the "sun" comes up, it inflates a thin membrane and starts to look more like a huge pin cushion.  The "skin" in this case is so thin that you can see through it.  It looks like a fine silk, with a sheen, and you can see the insides of the coral through the skin.  

This is what my Button Coral looked like when I first received it.  Not very inspiring.  Notice the "mouth" at the top.  The whole thing, rather than feeling like a lump of jello, feels like a rock (you have to handle them as you put them in the tank, like it or not).

As it starts to inflate, it begins to look like this:

In its full glory, it looks like this (along with a bonus-goby).

I fed it a small piece of turkey: this is how it reacted -- I guess it's not as hard as it looks!

Note that the colors in the above picture are more accurate.  Notice the translucent, iridescent greens and purples.  The white bars are a mystery to me: they are not visible in every "segment". One day it just decided to open its mouth for some reason.  Notice how those white bars (or disks?) are more visible and prominent now.

Quite mysterious and beautiful.  The pictures do not do it justice.  As you move your head around, the internal structure of the "pin cushion" is revealed as the iridescent colors change... One final shot.  The Button Coral is reputed to have small feeding tentacles near its mouth, but I've never seen them, even when I fed it.  Last night, after the lights turned off, I looked at the tank, and lo and behold...

Late breaking news.  The second time I fed the Button Coral, I fed it a piece of shrimp (Yikes: I'm a cannibal!) about half the size of a pencil eraser.  Here it is maneuvering its mouth to grab the morsel.

Here it is an hour or so after its meal. Notice the huge bulge in the middle: I'd never seen this before.  Also notice the small tentacles which clearly surround the oral disk, each tentacle tipped with a dot of yellow.