Megachilidae is a cosmopolitan family of mostly solitary bees. Characteristic traits of this family are the restriction of their pollen-carrying structure to the ventral surface of the abdomen, and their typically elongated labrum. Megachilid genera are most commonly known as mason bees and leafcutter bees, reflecting the materials from which they build their nest cells ; a few collect plant or animal hairs and fibers, and are called carder bees, while others use plant resins in nest construction and are correspondingly called resin bees. All species feed on nectar and pollen, but a few are kleptoparasites, feeding on pollen collected by other megachilid bees. Parasitic species do not possess scopae. The motion of Megachilidae in the reproductive structures of flowers is energetic and swimming-like; this agitation releases large amounts of pollen.
Mason bee is a name now commonly used for species of bees in the genus Osmia, of the family Megachilidae. Mason bees are named for their habit of using mud or other "masonry" products in constructing their nests, which are made in naturally occurring gaps such as between cracks in stones or other small dark cavities. When available, some species preferentially use hollow stems or holes in wood made by wood-boring insects.
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 individual cells for its brood that are separated by mud dividers. Unlike carpenter bees, it cannot drill holes in wood. O. lignaria is a common species used for early spring fruit bloom in the United States and Canada, though a number of other Osmia species are cultured for use in pollination.
The genus Megachile is a cosmopolitan group of solitary bees, often called leafcutter bees or leafcutting bees; it also includes the called resin bees and mortar bees. While other genera within the family Megachilidae may chew leaves or petals into fragments to build their nests, certain species within Megachile neatly cut pieces of leaves or petals, hence their common name. This is one of the largest genera of bees, with more than 1500 species in over 50 subgenera. The alfalfa leafcutter bee is managed on a commercial scale for crop pollination, and has been introduced by humans to various regions around the world.
Megachile sculpturalis, known as the giant resin bee and sculptured resin bee, is a species of leafcutting bees belonging to the family Megachilidae.
Osmia bicornis is a species of mason bee, and is known as the red mason bee due to its covering of dense gingery hair. It is a solitary bee that nests in holes or stems and is polylectic, meaning it forages pollen from various different flowering plants. These bees can be seen aggregating together and nests in preexisting hollows, choosing not to excavate their own. These bees are not aggressive; they will only sting if handled very roughly and are safe to be closely observed by children. Females only mate once, usually with closely related males. Further, females can determine the sex ratio of their offspring based on their body size, where larger females will invest more in diploid females eggs than small bees. These bees also have trichromatic colour vision and are important pollinators in agriculture.
Osmia cornuta, the European orchard bee, is a species of bee in the genus Osmia.
Osmia bicolor, the two-coloured mason-bee, is a Palearctic species of bee in the genus Osmia. It is outstanding amongst other megachilid bees in that it nests in empty snail shells.
Megachile fidelis, the faithful leafcutting bee, is a species of bee in the family Megachilidae.
Anthidium oblongatum, the oblong woolcarder bee, is a species of bee in the family Megachilidae, the leaf-cutter, carder, or mason bees. It is native to Eurasia and north Africa, and has also been introduced to North America.
Megachile campanulae, known as the bellflower resin bee, is a species of bee in the family Megachilidae. Described in 1903, these solitary bees are native to eastern North America. Studies in 2013 placed them among the first insect species to use synthetic materials for making nests. They are considered mason bees, which is a common descriptor of bees in several families, including Megachilidae. Within the genus Megachile, frequently also referred to as leafcutter bees, M. campanulae is a member of the subgenus Chelostomoides, which do not construct nests from cut leaves, but rather from plant resins and other materials. Females lay eggs in nests constructed with individual cell compartments for each egg. Once hatched, the eggs progress through larval stages and subsequently will overwinter as pupae. The bees are susceptible to parasitism from several other bee species, which act as brood parasites. They are medium-sized bees and the female adults are typically larger than the males. They are important pollinators of numerous native plant species throughout their range.
Euglossa cordata is a primitively eusocial orchid bee of the American tropics. The species is known for its green body color and ability to fly distances of over 50 km. Males mostly disperse and leave their home nests, while females have been observed to possess philopatric behavior. Because of this, sightings are rare and little is known about the species. However, it has been observed that adults who pollinate certain species of orchids will become intoxicated during the pollination.
Osmia uncinata, the pinewood mason bee, is a species of solitary bee from the family Megachilidae It is an Arctic-alpine species which is found in the northern Palearctic, in the United Kingdom it is a Biodiversity Action Plan priority species.
Osmia caerulescens, the blue mason bee, is a species of solitary bee from the family Megachilidae. It has a Holarctic distribution extending into the Indomalayan region, although its presence in the Nearctic may be due to human-assisted introduction.
Osmia inermis, the mountain mason bee , is a species of mason bee from the family Megachilidae which has a Holarctic distribution.
Osmia aurulenta is a Palearctic species of mason bee.
Osmia spinulosa, also known as the spined mason bee, is a species of bees within the genus Osmia.
Osmia parietina, also known as the Western mason bee or wall mason bee, is a species of solitary bee within the family Megachilidae.
Chrysura hirsuta, also known as the Northern Osmia ruby-tailed wasp, is a species of parasitic cuckoo wasp within the family Chrysididae.
Osmia nigriventris, also known as the large black-bellied mason bee, is a species of solitary bee within the family Megachilidae.
