This page is Canon.
Antlions are social creatures which live in large underground colonies. They include several subspecies, such as the Antlion Soldier, which is the most commonly found, the Antlion Worker, which works in nests and protects the Antlion Grubs, the larvaes, the Antlion Guard, a taller Antlion, and the Antlion Guardian, which rules the nests. Antlions are blind and use and vibrations to identify other living beings.
Behavior and skillsEdit
Common Antlions are the most visible element of a larger Antlion society, most of which is kept hidden in fiercely defended underground nests. It is not clear how Antlions breed. One resistance member is heard referring to a "spawning season" at the beginning of the Highway 17 chapter, but whether Antlions mate separately, have a or practice something completely alien to Earth sensibilities is not known. Their young begin life as larvae in blue honeycombs similar to those of bees. The extract of these larvae is highly prized by the Vortigaunts for its healing properties. The larvae grow into large grubs, which are attended to and protected by Antlion Workers and Antlion Guardians. Within this system, common Antlions presumably serve as hunter gatherers. Inside their nests, decomposed bodies of other creatures can often be discovered, trapped in the viscous silk the grubs produce as a food source, and some of their deepest chambers are pooled with blood.
Antlions were once farmed by Vortigaunts for their larval extract and a number of other purposes, possibly on their homeworld (no Xen creature is native from there the Victory Mine Vortigaunt states that Antlion husbandry was once their ancestral practice. Since the Combine invasion of Earth and the beginning of the Portal Storms the Antlions have established themselves on Earth. They have obviously been very successful in doing so, possibly to the point of causing extinction to other kinds of Earth fauna. So widespread were the Antlions on Earth that the Combine had to install a large network of thumpers around Nova Prospekt, as well as a vast variation to the base of the Citadel. When these were shut down by Gordon Freeman's activities, both Nova Prospekt and City 17 were quickly overrun separately by Antlions, with chaotic results.