Strange growths.

I have a lot of different crap growing in my tank at the moments but in particular I would like to know what these things are.
They are about a quarter of an inch long with a tail of about 3 to 4 inches. This is the best pic I could get.

 

I get the impression you believe them to be animal not plant?

 

I have no idea, I just used the term tail as a way to describe it. I doubt that they are animal though because they stay in the same spot.

 

It's algae.

The "tail" is algae growing in scratches in the glass/acrylic.

 

Thank you.
Great another type of algae to add to the list.

 

Just part of (presumably) new tank syndrome. Nothing to worry about really.

 

Thank you all for the replies.
It is a relatively new tank (about 8 months).
I downgraded to a smaller setup to cut down on the relentless maintenance, it hasn't been cut down by much.