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).
Cuckoo bees typically enter the nests of pollen-collecting species, and lay their eggs in cells provisioned by the host bee. When the cuckoo bee larva hatches it consumes the host larva's pollen ball, and, if the female kleptoparasite has not already done so, kills and eats the host larva. In a few cases in which the hosts are social species (e.g., the subgenus Psithyrus of the genus Bombus, which are parasitic bumble bees, and infiltrate nests of non-parasitic species of Bombus), the kleptoparasite remains in the host nest and lays many eggs, sometimes even killing the host queen and replacing her – such species are often called social parasites, although a few of them are also what are referred to as "brood parasites."
Many cuckoo bees are closely related to their hosts, and may bear similarities in appearance reflecting this relationship. This common pattern gave rise to the ecological principle known as "Emery’s Rule". Others parasitize bees in families different from their own, like Townsendiella, a nomadine apid, one species of which is a kleptoparasite of the melittid genus Hesperapis, whereas the other species in the same genus attack halictid bees.
The term cuckoobee is used for a variety of different bee lineages which have evolved the kleptoparasitic behaviour of laying their eggs in the nests...
stingless bees (also used for honey production), carpenter bees, orchid bees, cuckoobees, and a number of other less widely known groups. Many are valuable...
host bee. When the "cuckoo" bee larva hatches, it consumes the host larva's pollen ball, and often the host egg also. In particular, the Arctic bee species...
are known to enter bee nests and feed on the provisions reserved for the bee larva. True brood parasitism is rare among insects. Cuckoo bumblebees (the subgenus...
Bombus sylvestris, known as the forest cuckoo bumblebee or four-coloured cuckoobee, is a species of cuckoo bumblebee, found in most of Europe and Russia...
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...
commonly known as the neon cuckoobee, is a parasitic bee of the genus Thyreus, called cuckoobees. It is a stocky bee, notable for its brilliant metallic...
analysis of cuckoo wasps (Hymenoptera: Chrysididae) reveals a partially artificial classification at the genus level and a species‐rich clade of bee parasitoids"...
kleptoparasites are arthropods, especially bees and wasps, but including some true flies, dung beetles, bugs, and spiders. Cuckoobees are specialized kleptoparasites...
and its nest parasite the cuckoobee Nomada armata. This is a rare inland site for the nationally scarce brown-banded carder bee (Bombus humilis), and the...
Australian native bees are a group of bees that play a crucial role in the pollination of native plants. There are over 1,700 species of native bees in Australia...
commonly known as the chequered cuckoobee, is a parasitic bee of the genus Thyreus, also called cuckoobees. It is a stocky bee, notable for its brilliant...
Osmia lignaria, commonly known as the orchard mason bee or blue orchard bee, is a megachilid bee that makes nests in natural holes and reeds, creating...
neon cuckoobee Thyreus nitidulus. Human activity, for example the clearing of river banks in the Caboolture River, may threaten nest sites of this bee. "Species...
before the female. The nests are frequently invaded by cleptoparasitic "cuckoobees". Dallas, William Sweetland (1857). Elements of entomology: an outline...
which attempt to usurp its nest. All cuckoo bumblebee species lack a worker caste—instead the female queen cuckoobee invades the nest of a host species...
largest genera in the family Apidae, and the largest genus of cuckoobees. Cuckoobees are so named because they enter the nests of a host and lay eggs...
Epeolus howardi, or Howard's cellophane-cuckoobee, is a species of cuckoobee in the family Apidae. It is found in North America. "Epeolus howardi Report"...
bear bee adds an egg to each with a food supply of pollen and nectar paste. Nesting individuals of species are stalked by the domino cuckoobee (Thyreus...
later. These species are themselves specifically parasitised upon by the cuckoobee Biastes brevicornis. Outside its native range, field bindweed does not...
the cuckoobees, which includes 29 species found in Europe and the New World. Species in this subgenus are obligate parasites of other bumble bees. The...
name red-legged cuckoo leafcutter bee, is a species of bee in the family Megachilidae. It is native to North America. This cuckoobee parasitizes the...
variety of bees, including little carpenter bees, cuckoobees, halictine bees, and masked bees; as well as flies, including syrphid flies, bee flies, tachinid...
mimicry would be cuckoobees (genus: Nomada). Cuckoobees will parasitize bees of the families Melittidae and Andrenidae. Cuckoobee males will produce...
Leiopodus singularis is a species of bee in the family Apidae. It is found in Central America and North America. This species is a kleptoparasite of Diadasia...
(bees and sphecoid wasps) Family Ampulicidae (cockroach wasps) Family Andrenidae (mining bees) Family Apidae (carpenter bees, digger bees, cuckoobees...