I use stargrass as a groundcover... Looks nice, have to prune it when it gets a couple inches long (every 1-2 weeks)... but does well with 1-2 wpg and no co2 or ferts in my tank.
although, it doesn't look anything like whats in the photo.
maybe cratonneuron filicinum aka spike moss?
where are you from?
in the US, you can browse sweet aquatics... (www.sweetaquatics.com
for a nano tank, foregrounds are mostly limited to mosses unless you want to prune something like stargrass 1-2 times a week....
starmoss, riccia, and maybe dwarf baby tears (baby tears needs high light)
as far as I can tell, the plant you're interested in is "utricularia graminfolia"