Tiny white spiderweb living in tonga branch

[Feron]

Ok, I just got a load of live rock, and it included a couple pieces of tonga branch... one looked almost devoid of anything on it's surface, except for tiny pinholes all over it..

I noticed yesterday a small, maybe 2mm, web like thing.. seems pretty symetrical with I think an outer ring and inner ring of white dots around almost clear radials. It appears to be connected.
It's coming out of one of the tiny pores in the rock, and when startled (by a flashbulb) it retracts rather quickly.
I've also seen it retracts on it's own, so I am assuming it is some sort of filter feeder.
It doesn't appear to have a stalk, the 'web' is barely a mm off the rock when the thing is extended. (hoping it isn't a really really really tiny aptasia)
It's so tiny it is hard to get the camera focused on it to take a decent picture. I broke out the camcorder and got an o.[acronym:551d40b9dd="Kelvin or Potassium, depending on context"]k[/acronym:551d40b9dd]. shot of it that I will take a frame from and post it.

Any ideas?

[Fluff]

A worm of some sort would be my guess. Perhaps a spaghetti worm. Aptasia wouldn't startle, at least in my experience with them, at the light of a flashlight.