If I know plants, and I'd like to think I do - especially Anubias, that looks like a anubias afzelii - congensis - or lanceolata.
Had a similar one in my old Anubias tank, not my personal favorite.
I also think for the image you have, the roots look pretty bad in shape - hence why they look almost like fern roots, if it is an Anubias cut those roots off (which you should for most plants), leave about a cm in length and wash them clean. Those roots grow like weeds.
It got mixed up with crypts and was planted for a long while, that probably hurt the roots and growth. I have multiple tanks growing plants to sell and things get moved around a lot or left alone for a long time.
I had an anubias and I thought I had sold it as a crypt by mistake, thinking this is that plant.
I does have a large rhizome like anubias, that is what got my attention when I saw it.
take some more pics dude, you will get a better answer. The roots def look like a fern(unless just rotten roots), but leafs/ rhizone look like a anubius. But I would go with Defaults answer so far, it makes the most sense.