mystery plant

Hi there! Earlier today I went to the LFS to buy a plant, and bought this guy for 7.99. I'm now regretting getting it because it just doesn't fit. Can someone id it? Thanks!

I have a 55 gallon aquarium kept at ~78-80 Degrees F on a 12 hour light cycle with multiple root tabs but no water fertilizer. The aquarium isn't fully cycled yet. My Duckweed and Anubias plants are doing great... but my Java Fern, Monte Carlo, and some other plant that I got at Petco are not...