What am I?

Some kind of worm, I searched through that hitchhiker worm thread but couldnt find a solid ID. Maybe someone here could help?? I only see it once in a blue moon and crawling over the rockwork only. Seems to cling to the rock and I have not seen it lift a bodypart off of the rock at any given time. It looks kind of fluorescent first photo is with flash other 2 without.





Its not very big maybe a couple inches. Just want to know if its a good guy or bad guy and if possible what it is

 

brittle star arm?

can you take it of the rock if you want?

 

Like from a starfish?? I never had any in my tank and its been unchanged for months. Also do brittle stars have that purplish glow to them and look so segmental?

 

Yup brittle star.

They seldom expose their entire body. Very common to see them hanging out their legs to catch food.

It's a good bet you have many more and you just never see them.

Harmless scavengers.

 

Makes sense but what you see in the picture I am 99% sure if the entire thing. I have seen both ends move and crawl around on the rock. I guess it is possible to jsut be an arm with part of the center attached??

 

sorry for late respones, but +1 to corailline