From Halopedia, the Halo wiki
A Hive Queen, commonly referred to simply as a queen, is the matriarchal ruling caste of a Yanme'e hive. Yanme'e queens are extremely large, with elongated, distended abdomens and thick legs, requiring the support of subservient males carrying them on cushioned litter for transport.
When the Yanme'e first contacted the Covenant in 1112, a bloody war began. However, after an assembly was formed among the Hive Queens on Palamok, they decided to allow lower-caste Yanme'e to be employed by the Covenant.
While rarely seen among the other Covenant species otherwise, Yanme'e queens were known to participate in some particularly significant occasions, such as the ascension ceremony of the High Prophets of Truth, Regret, and Mercy on High Charity. During the Human-Covenant War, the scientist Sig Raan created a device that mimicked the sonic and pheromonal signals of a Hive Queen, although the device was destroyed by Atriox when Raan turned the Yanme'e under her control against the Banished.
Function and role
While Yanme'e are individually cunning and moderately intelligent, they can exhibit extremely complicated behaviors when organized by a queen. The Hive Queen controls her hive through the use of sonic and pheromonal signals. The queens are at the top of the species' linear power structure and lead over all other Yanme'e, and all other Yanme'e were subjected to the will of the Hive Queen.
Yanme'e society is organized around their queens. The Yanme'e lead an aggressively matriarchal society, with all other castes supporting their hives' preservation through the orders of a queen. Yanme'e queens are responsible for the species' reproduction and way of life, leading to the well-being of a queen being the uppermost importance of a hive. Most of the Yanme'e's major scientific and technological advances have emphasized protection on the queen and augmentation of the hives.
List of appearances