Is this a feather duster worm?

[I Eat Ice Cubes]

So today I got a new light, and while I was setting up the tank, all my coral polyps retracted because of the constant light change. During this time I noticed that my hammer coral has some funky looking fellow between it's heads. I'm assuming it's a feather duster, but my tank is super new (3 months+) so I thought there would be no way it wouldn't starve. If anyone can ID it for me that would be awesome! (and if anyone can tell me what those white lines are that would be great too)

 

[JGT]

Yes, featherduster. The white lines are also tubes for micro featherdusters.

 

[SlugSnorter]

So today I got a new light, and while I was setting up the tank, all my coral polyps retracted because of the constant light change. During this time I noticed that my hammer coral has some funky looking fellow between it's heads. I'm assuming it's a feather duster, but my tank is super new (3 months+) so I thought there would be no way it wouldn't starve. If anyone can ID it for me that would be awesome! (and if anyone can tell me what those white lines are that would be great too)View attachment 2623269

could starve, but should be fine since this is one of the smaller more hardy ones.