Colobopsis

also known as cork-head ants, these arboreal ants live in wood, small and large dead branches, galls, etc., in which they carve galleries; the which open to the surface of the wood always have the exact diameter of the anterior truncation of the head of majors and queens. A soldier, or the queen, keeps custody over the nest, that is to say, seals the hole with her head, and retires into the nest tunnel to allow sisters to pass.