A bumblebee is any of over 250 species in the genus Bombus, part of Apidae, one of the bee families. This genus is the only extant group in the tribe Bombini, though a few extinct related genera (e.g., Calyptapis) are known from fossils. They are found primarily in higher altitudes or latitudes in the Northern Hemisphere, although they are also found in South America where a few lowland tropical species have been identified. European bumblebees have also been introduced to New Zealand and Tasmania.

Queen and worker bumblebees can sting. Unlike in honeybees, a bumblebee's sting lacks barbs, so the bee can sting repeatedly without injuring itself; by the same token, the sting is not left in the wound. Bumblebee species are not normally aggressive, but may sting in defence of their nest, or if harmed.

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