Formian

From NWNWiki

Formians are dimensional travelers that come from a plane devoted to law. Their colonies include: Workers, who make up most of the population; Taskmasters, who drive the Workers; Soldiers, who fiercely protect the colony and queen; Myrmarchs, who are intelligent enough to have learned the use of magic; and the Queen, who leads the whole colony. They are ruthlessly expansionist, though not actually evil.

A formian resembles a strange, centaur-like creature with the body and head of a giant ant, but with humanoid forelimbs. Their bodies are encased in in a brownish-red, black, or white carapace. Formains are not cruel but live in a strict, regimented society.