Megachile (Megachile)

Taxonomy

Family: Megachilidae
Subfamily: Megachilinae
Tribe: Megachilini
Genus: Megachile Latreille, 1802
Subgenus: Megachile Latreille, 1802
Common name: none

Overview

Megachile (Megachile) are “ordinary-looking” bees with black integumentintegument:
a tough, protective outer layer
, primarily pale hair on their bodies, and white apicalapical:
near or at the apex or end of any structure
hair bandsbands:
usually referring to bands of hair or bands of color that traverse across an abdominal segment
on their tergaterga:
the segments on the top side of the abdomen, often abbreviated when referring to a specific segment to T1, T2, T3, T4, T5, T6, or T7
(Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.). They range in body length from 7–20 mm (Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.).

Diagnostic characteristics

(modified from Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.; Praz 2017Praz 2017:
Praz, C.J. 2017. Subgeneric classification and biology of the leafcutter and dauber bees (genus Megachile Latreille) of the western Palearctic (Hymenoptera, Apoidea, Megachilidae). Journal of Hymenoptera Research 55: 1-54.)

• Female mandiblemandible:
  bee teeth, so to speak, usually crossed and folded in front of the mouth
  is four- or five-toothed with an incomplete cutting edge in the second interspace (except in Megachile montivaga, which has no cutting edges) and usually no visible cutting edge in the third interspace.
• Female scopascopa:
  modified hairs for carrying pollen; often branched and dense hairs on the hind-leg, or on the ventral surface of the abdomen in Megachilidae
  usually orange-red on S1–S4, although it can sometimes be white and can be black on S6S6:
  the plates on the underside of the abdomen, often abbreviated when referring to a specific segment to S1, S2, S3, S4, S5, S6, S7, or S8
  and often S5S5:
  the plates on the underside of the abdomen, often abbreviated when referring to a specific segment to S1, S2, S3, S4, S5, S6, S7, or S8
  .
• Female sternasterna:
  the plates on the underside of the abdomen, often abbreviated when referring to a specific segment to S1, S2, S3, S4, S5, S6, S7, or S8
  without apicalapical:
  near or at the apex or end of any structure
  hair bandsbands:
  usually referring to bands of hair or bands of color that traverse across an abdominal segment
  beneath the scopascopa:
  modified hairs for carrying pollen; often branched and dense hairs on the hind-leg, or on the ventral surface of the abdomen in Megachilidae
  .
• Female T6T6:
  the segments on the top side of the abdomen, often abbreviated when referring to a specific segment to T1, T2, T3, T4, T5, T6, or T7
  usually straight in profile.
• Female tarsal claw with two basalbasal:
  originating at the foundation of a structure
  setae, the innermost setaesetae:
  a still hair-like structure or bristle
  modified to a short thickened process.
• Male front coxacoxa:
  the basal segment of the leg
  without a spine.
• Male mandiblemandible:
  bee teeth, so to speak, usually crossed and folded in front of the mouth
  three-toothed, often with a basalbasal:
  originating at the foundation of a structure
  projection on the lower margin.
• Male T6T6:
  the segments on the top side of the abdomen, often abbreviated when referring to a specific segment to T1, T2, T3, T4, T5, T6, or T7
  with preapicalpreapical:
  referring to a section of a bee that is physically found just before the outermost (or apical) end of the section or segment
  carinacarina:
  a clearly defined ridge or keel, not necessarily high or acute; usually appears on bees as simply a raised line
  smooth, not denticulatedenticulate:
  a small tooth-like projection
  , and sometimes emarginateemarginate:
  a notched or cut out place in an edge or margin, can be dramatic or simply a subtle inward departure from the general curve or line of the margin or structure being described
  medially.

May be confused with

Megachile (Megachile) is similar looking to Megachile (Litomegachile) in their general appearance with overall pale hair and tapered abdomen with white apicalapical:
near or at the apex or end of any structure
hair bandsbands:
usually referring to bands of hair or bands of color that traverse across an abdominal segment
(Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.). Female M. (Megachile) can be differentiated by their mandibles, which do not have the cutting edges in the third interspace that are present in M. (Litomegachile). Male M. (Megachile) can be separated by the front coxacoxa:
the basal segment of the leg
that does not have a spine (Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.).

Host associations

Megachile (Megachile) have been observed visiting flowers from multiple plant families, including Apiaceae, Asteraceae, Cactaceae, Campanulaceae, Cardueae, Cucurbitaceae, Ericaceae, Fabaceae, Geraniaceae, Malvaceae, Onagraceae, Ranunculaceae, Rosaceae, Rubiaceae, Solanaceae, and Verbenaceae (Mitchell 1935bMitchell 1935b:
Mitchell, T.B. 1935. A revision of the genus Megachile in the Nearctic region. Part III. Taxonomy of subgenera Anthemois and Delomegachile (Hymenoptera: Megachilidae). Transactions of the American Entomological Society 61(3): 155-205.; Müller and Bansac 2004).

Nesting behavior

Megachile (Megachile) nest in pre-existing cavities in wood or pithy stems, or excavate their own cavities in sandy soils; some species are flexible in their choice of nest site and will nest in either cavities above ground or in soil (Mitchell 1935aMitchell 1935a:
Mitchell, T.B. 1935. A revision of the genus Megachile in the Nearctic region. Part II. Morphology of the male sternites and genital armature and the taxonomy of the subgenera Litomegachile, Neomegachile and Cressoniella (Hymenoptera: Megachilidae). Transactions of the American Entomological Society 61: 1-44.; Sheffield and Westby 2007Sheffield and Westby 2007:
Sheffield, C.S. and S.M. Westby. 2007. The male of Megachile nivalis Friese, with an updated key to members of the subgenus Megachile s. str. (Hymenoptera: Megachilidae) in North America. Journal of Hymenoptera Research 16(1): 178-191.; Praz 2017Praz 2017:
Praz, C.J. 2017. Subgeneric classification and biology of the leafcutter and dauber bees (genus Megachile Latreille) of the western Palearctic (Hymenoptera, Apoidea, Megachilidae). Journal of Hymenoptera Research 55: 1-54.). Brood cells are usually constructed using small, circular pieces of leaves (Gonzalez 2008Gonzalez 2008:
Gonzalez, V.H. 2008. Phylogeny and classification of the bee tribe Megachilini (Hymenoptera: Apoidea: Megachilidae), with emphasis on the genus Megachile. Thesis: Department of Ecology and Evolutionary Biology and the College of Liberal Arts and Science of the University of Kansas: 1-274.). Megachile (Megachile) montivaga is unique in that it is known to use flower petals instead of leaves to make its nest cells (Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.; Orr et al. 2015Orr et al. 2015:
Orr, M.C., Z.M. Portman, and T. Griswold. 2015. Megachile ( Megachile ) montivaga (Hymenoptera: Megachilidae) nesting in live thistle (Asteraceae: Cirsium ). Journal of Melittology 48: 1-6.).

Diversity

Megachile (Megachile) includes 31 species (Ascher and Pickering 2020Ascher and Pickering 2020:
Ascher, J.S. and J. Pickering. 2020. Discover Life bee species guide and world checklist (Hymenoptera: Apoidea: Anthophila). https://www.discoverlife.org/mp/20p?see=Carinulaamp;name=Megachileamp;flags=subgenus :).

Known invasives

There are no known invasives.

Distribution

Megachile (Megachile) is HolarcticHolarctic:
biogeographic region that encompasses the majority of habitats found throughout the northern continents of the world
and can be found throughout North America and Europe, as well as northern Africa and Asia. They primarily occur in cool areas (Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.).

​Distribution map generated by Discover Life -- click on map for details, credits, and terms of use.

References

Ascher, J.S. and J. Pickering. 2020. Discover Life bee species guide and world checklist (Hymenoptera: Apoidea: Anthophila). https://www.discoverlife.org/mp/20p?see=Megachile&name=Megachile&flags=subgenus:

Gonzalez, V.H. 2008. Phylogeny and classification of the bee tribe Megachilini (Hymenoptera: Apoidea: Megachilidae), with emphasis on the genus Megachile. Thesis: Department of Ecology and Evolutionary Biology and the College of Liberal Arts and Science of the University of Kansas: 1-274.

Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.

Mitchell, T.B. 1935. A revision of the genus Megachile in the NearcticNearctic:
biogeographical region comprising North America as far south as northern Mexico, together with Greenland
region. Part III. Taxonomy of subgenera Anthemois and Delomegachile (Hymenoptera: Megachilidae). Transactions of the American Entomological Society 61(3): 155-205.

Müller, A. and N. Bansac. 2004. A specialized pollen-harvesting device in western palaearctic bees of the genus Megachile (Hymenoptera, Apoidea, Megachilidae). Apidologie 35: 329-337.

Orr, M.C., Z.M. Portman, and T. Griswold. 2015. Megachile (Megachile) montivaga (Hymenoptera: Megachilidae) nesting in live thistle (Asteraceae: Cirsium). Journal of Melittology 48: 1-6.

Praz, C.J. 2017. Subgeneric classification and biology of the leafcutter and dauber bees (genus Megachile Latreille) of the western PalearcticPalearctic:
the largest biogeographic region; consists of Europe, Asia north of the Himalaya foothills, Northern Africa, and the northern and central parts of the Arabian Peninsula
(Hymenoptera, Apoidea, Megachilidae). Journal of Hymenoptera Research 55: 1-54.

Sheffield, C.S. and S.M. Westby. 2007. The male of Megachile nivalis Friese, with an updated key to members of the subgenus Megachile s. str. (Hymenoptera: Megachilidae) in North America. Journal of Hymenoptera Research 16(1): 178-191.