most of subtropical Central America and Mexico. They are also found in southeastern Arizona and the most southern counties of Texas. It builds its nest in the canopy of a shrub or a tree, often 1 to 9 m above the ground. Nests are often reported to be located in suburban settings that are close to human habitation. They are well covered in the foliage in which they are built. These nests can be threatened by urban development, such as in Texas. Colony cycle Nests of B. mellifica can have anywhere from 3,500 to 18,700 wasps. Populations are abundant during July and September, which are times associated with plentiful citrus groves and thus large populations of the psyllid Diaphorina citri, a common prey of B. mellifica. When the D. citri nymphs are not plentiful, the wasps nearly disappear until D. citri populations return the following spring. Clusters of colonies of B. mellifica are common, which suggests that swarms may only travel several hundred meters to start a new colony. According to some sources, it is not apparent whether queens start new colonies independently or if they intrude on another colony. Queens either mate and reproduce in their original colony, or can split off with a number of workers, in order to found a new colony via swarming. Males do also remain in their biological colonies and do not travel to other colonies to seek matings. Depending on the ratio of workers to queens in the colony, queens will regulate the number of new queens and workers raised. New queens are not produced unless there is only one queen remaining, following a cyclical monogyny colony cycle. Like most eusocial hymenoptera, communities of B. mellifica consist predominantly of sterile female workers and relatively few male drones and queens. The number of fertilized queens can range into the hundreds in B. mellifica colonies. The high relatedness of a given colony's queens may indicate that such queens are only produced in the colony when there is a single queen. Colonies with a single queen have not been reported, indicating that if such a condition exists that it is a short-lived period in the colony's life cycle. Kin selection and genetic relatedness within colonies Queen to worker relatedness Queens within a single colony are highly related, which is consistent with the hypothesis that queens are only produced when the colony contains one queen. In a