Honeypot ant

Honeypot ants, also called honey ants, are ants which have specialized workers (repletes,plerergates, or rotunds) that are gorged with food by workers to the point that their abdomens swell enormously. Other ants then extract nourishment from them. They function as living larders. Honeypot ants belong to any of several genera, including Myrmecocystus and Camponotus. They were first documented in 1881 by Henry C. McCook, and described further in 1908 by William Morton Wheeler.

Many insects, notably honey bees and some wasps, collect and store liquid for use at a later date. However, these insects store their food within their nest or in combs. Honey ants are unique in using their own bodies as living storage, used later by their fellow ants when food is otherwise scarce. When the liquid stored inside a honeypot ant is needed, the worker ants stroke the antennae of the honeypot ant, causing the honeypot ant to regurgitate the stored liquid from its crop.

The abdomen of species like Camponotus inflatus consists of hard dorsal sclerites (stiff plates) connected by a softer, more flexible arthrodial membrane. When the abdomen is empty, the arthrodial membrane is folded and the sclerites overlap, but when the abdomen fills the arthrodial membrane becomes fully stretched, leaving the sclerites widely separated.

Myrmecocystus nests are found in a variety of arid or semiarid environments. Some species live in extremely hot deserts, others reside in transitional habitats, and still other species can be found in woodlands which are somewhat cool but still very dry for a large part of the year. For instance, the well-studied Myrmecocystus mexicanus resides in the arid and semiarid habitats of the southwestern U.S. Sterile workers in this species act as plerergates or repletes during times of food scarcity. When the pleregates are fully engorged, they become immobile and hang from the ceilings of the underground nests. Other workers drain them of their liquid food stores to feed the rest of the colony. Plerergates can live anywhere in the nest, but in the wild, they are found deep underground, unable to move, swollen to the size of grapes.

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