The Bugs in the film differ considerably from those in the novel, which calls the Bugs "Pseudo-Arachnids". Meanwhile, Mongoose Publishing's Starship Troopers: The Miniatures Game refers to them as the Arachnid Empire or the Bug Empire. In the third film in the franchise, the bugs are referred to as "Archie", similar to nicknames given to Germans ("Jerry") and the Viet Cong ("Charlie") in their respective wars. The novel's Bugs are highly susceptible to radiation and chemical attacks, and the Mobile Infantry frequently seals their escape holes.
In the films, the Arachnid Quarantine Zone consists of many star systems colonized by the Arachnids. At some point "plasma" bugs developed the ability to fire spores into orbit. Utilizing a bioshipstar drive, the spores can travel to other systems and impact with planets, thus spreading Arachnid eggs and creating a new generation of bugs.
In the first film, Klendathu, Tango Urilla, and Planet P are the only worlds explicitly shown to be colonized by Arachnids, although an unspecified number of planets are under their control. It is also shown that they slaughtered a colony of "Mormon extremists" on a planet called Dantana. In the TV show, multiple celestial bodies, including Pluto and fictional planets, are inhabited by the Bugs.