Bombus citrinus is a species of bumblebee known commonly as the lemon cuckoo bumblebee due to its lemon-yellow color. It is native to eastern North America.

This is a cuckoo bumblebee, one that invades the colonies of other bumblebees, kills the resident queen, and takes control over the population of workers inside. Host bees for this species include the common eastern bumblebee (Bombus impatiens) and the half-black bumblebee (B. vagans).

Before the queen invades a nest she forages on various plants, such as asters, thistles, snakeroots, blazing-stars, mountain-mints, and goldenrods.

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