For some reason, the Fusilaut, like all the airdrop assault rifles, uses Ranger Magazines. The real life counter part uses STANAG Mags (aka the in-game Military Magazines). The most sensible explanation is that those weapons have been modified to use ranger magazines and ammunition.
Due to this difference, the Fusilaut can hold 35 rounds, unlike its counterpart's 25.
It appears to be based off the Nexter FAMAS G2 in use by the French Armed Forces.
Its name may come from the word "fusillade" and the French words "fusil d'assault", meaning "a series of shots in succession" and "assault rifle" respectively.
The Fusilaut is one of three bullpup designed weapons.