Apidae in the context of Apini

A honey bee (also spelled honeybee) is a eusocial flying insect from the genus Apis of the largest bee family, Apidae. Honey bees are known for their construction of perennial nests within cavities (i.e. beehives) containing hexagonal cells made of secreted wax, their large colony sizes, and their routine regurgitation of digested carbohydrates as surplus food storage in the form of honey, the lattermost of which distinguishes their hives as a prized foraging target of many mellivorous animals including honey badgers, bears and human hunter-gatherers.

Although honey bees represent only a small fraction of the roughly 20,000 known species of bees, they are the bee clade most familiar to humans and are also the most valuable beneficial insects to agriculture and horticulture. The best-known honey bee species is the western honey bee (Apis mellifera), which was domesticated and farmed (i.e. beekeeping) for honey production and crop pollination. The only other domesticated species is the eastern honey bee (Apis cerana), which are raised in South, Southeast and East Asia.

A bumblebee (or bumble bee, bumble-bee, or humble-bee) 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 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. Female bumblebees can sting repeatedly, but generally ignore humans and other animals.

Most bumblebees are eusocial insects that form colonies with a single queen. The colonies are smaller than those of honey bees, growing to as few as 50 individuals in a nest. Cuckoo bumblebees are brood parasitic and do not make nests or form colonies; their queens aggressively invade the nests of other bumblebee species, kill the resident queens and then lay their own eggs, which are cared for by the resident workers. Cuckoo bumblebees were previously classified as a separate genus, but are now usually treated as members of Bombus.

Stingless bees (SB), sometimes called stingless honey bees or simply meliponines, are a large group of bees (from about 462 to 552 described species), comprising the tribe Meliponini (or subtribe Meliponina according to other authors). They belong in the family Apidae (subfamily Apinae), and are closely related to common honey bees (HB, tribe Apini), orchid bees (tribe Euglossini), and bumblebees (tribe Bombini). These four bee tribes belong to the corbiculate bees' monophyletic group. Meliponines have stingers, but they are highly reduced and cannot be used for defense, though these bees exhibit other defensive behaviors and mechanisms. Meliponines are not the only type of bee incapable of stinging: all male bees and many female bees of several other families, such as Andrenidae and Megachilidae (tribe Dioxyini), also cannot sting.

Some stingless bees have strong mandibles and can inflict painful bites. Some species can present large mandibular glands for the secretion of caustic defense substances, secrete unpleasant smells or use sticky materials to immobilise enemies.

Nomadinae is a subfamily of bees in the family Apidae. They are known commonly as cuckoo bees.

This subfamily is entirely kleptoparasitic. They occur worldwide, and use many different types of bees as hosts. As parasites, they lack a pollen-carrying scopa, and are often extraordinarily wasp-like in appearance. All known species share the behavioral trait of females entering host nests when the host is absent, and inserting their eggs into the wall of the host cell; the larval parasite emerges later, after the cell has been closed by the host female, and kills the host larva. The first-instar larvae of nomadines are specially adapted for this, and possess long mandibles they use to kill the host larva, though these mandibles are lost as soon as the larva molts to the second instar, at which point it simply feeds on the pollen/nectar provisions. A behavioral habit shared by adults of various genera with males of many other bee species, who also do not possess a nest to return to, is that they frequently rest while grasping onto plant stems or leaves with only their mandibles.

The Bombini are a tribe of large bristly apid bees which feed on pollen or nectar. Many species are social, forming nests of up to a few hundred individuals; other species, formerly classified as Psithyrus cuckoo bees, are brood parasites of nest-making species. The tribe contains a single living genus, Bombus, the bumblebees, and some extinct genera such as Calyptapis and Oligobombus. The tribe was described by Pierre André Latreille in 1802.

The Apinae are the subfamily that includes the majority of bees in the family Apidae. It includes the familiar "corbiculate" (pollen basket) bees—bumblebees, honey bees, orchid bees, stingless bees, and the extinct genus Euglossopteryx. It also includes all but two of the groups (excluding Nomadinae and Xylocopinae) that were previously classified in the family Anthophoridae.

Most species in the subfamily (other than honey bees, bumblebees, and stingless bees) are solitary, though several of the tribes are entirely kleptoparasitic, such as the Ericrocidini, Isepeolini, Melectini, Osirini, Protepeolini, and Rhathymini.

The term cuckoo bee is used for a variety of different bee lineages which have evolved the kleptoparasitic behaviour of laying their eggs in the nests of other bees, reminiscent of the behavior of cuckoo birds. The name is perhaps best applied to the apid subfamily Nomadinae, but is sometimes used in Europe to mean bumblebees (Bombus) in the subgenus Psithyrus. Females of cuckoo bees are easy to recognize in almost all cases, as they lack pollen-collecting structures (the scopa) and do not construct their own nests. They often have reduced body hair, abnormally thick and/or heavily sculptured exoskeleton, and saber-like mandibles, although this is not universally true; other less visible changes are also common.

The number of times kleptoparasitic behavior has independently evolved within the bees is remarkable; Charles Duncan Michener (2000) lists 16 lineages in which parasitism of social species has evolved (mostly in the family Apidae), and 31 lineages that parasitize solitary hosts (mostly in Apidae, Megachilidae, and Halictidae), collectively representing several thousand species, and therefore a very large proportion of overall bee diversity. There are no cuckoo bees in the families Andrenidae, Melittidae, or Stenotritidae, and possibly the Colletidae (there are only unconfirmed suspicions that one group of Hawaiian Hylaeus species may be parasitic).