I needed to transplant and propagate these Congo Anubias. They were growing in a bed of Java Moss and other plants but this other plant volunteered and appeared in growbed. It resembles dwarf hair grass, you can see in second pic.
I dont think its guppy grass, this plant had long unsegmented sections and only grew in the darkest sections of growbed. In the picture it's the less green plant on the left of picture. I grow guppy grass too. Here's a pic.