Megachile (Megachiloides)

Taxonomy

Family: Megachilidae
Subfamily: Megachilinae
Tribe: Megachilini
Genus: Megachile Latreille, 1802
Subgenus: Megachiloides Mitchell, 1924
Common name: none

Overview

Megachile (Megachiloides) are medium-sized, megachiliformmegachiliform:
body heavy, head thick, metasoma rather wide, not parallel-sided
bees with black integumentintegument:
a tough, protective outer layer
and often with pale 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 the 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
. They range in body length from 9–17 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 Mitchell 1933Mitchell 1933:
Mitchell, T.B. 1933. A revision of the genus Megachile in the Nearctic region Part I: classification and descriptions of new species (Hymenoptera: Megachilidae). Transactions of the American Entomological Society 59: 295ndash;361.; Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.; 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.)

• Preoccipital carinacarina:
  a clearly defined ridge or keel, not necessarily high or acute; usually appears on bees as simply a raised line
  absent.
• Female clypeusclypeus:
  a section of the face below the antennae, demarcated by the epistomal sutures
  with a straight or slightly crenulatecrenulate:
  having a finely scalloped or notched outline or edge
  apicalapical:
  near or at the apex or end of any structure
  margin.
• Female mandiblemandible:
  bee teeth, so to speak, usually crossed and folded in front of the mouth
  three- or four-toothed with a long, complete cutting edge in the innermost interspace (second or third interspace depending on the number of teeth).
• Female mandiblemandible:
  bee teeth, so to speak, usually crossed and folded in front of the mouth
  with inner-most tooth acute.
• 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
  .
• Female 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
  with hair well dispersed throughout the segment.
• 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
  straight in profile.
• Male front coxacoxa:
  the basal segment of the leg
  with a spine.
• Male front tarsitarsi:
  the group of segments at the end of the leg following the tibia
  usually distinctly expanded.
• Male mandiblemandible:
  bee teeth, so to speak, usually crossed and folded in front of the mouth
  three- or four-toothed with a basalbasal:
  originating at the foundation of a structure
  projection on the lower margin.
• Male S4S4:
  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 a median apicalapical:
  near or at the apex or end of any structure
  tubercle.
• 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
  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
  is entire, without a median emarginationemargination:
  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
  , and can be crenulatecrenulate:
  having a finely scalloped or notched outline or edge
  or denticulatedenticulate:
  a small tooth-like projection
  .
• Male T7T7:
  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 acutely pointed.

Host associations

Megachile (Megachiloides) have been observed visiting flowers from multiple plant families including: Asteraceae, Cactaceae, Chrysobalanaceae, Fabaceae, Gentianaceae, Malvaceae, Onagraceae, Verbenaceae, and Zygophyllaceae (Mitchell 1936Mitchell 1936:
Mitchell, T.B. 1936. A revision of the genus Megachile in the Nearctic region. Part IV. Taxonomy of subgenera Xanthosarus, Phaenosarus, Megachiloides and Derotropis (Hymenoptera: Megachilidae). Transactions of the American Entomological Society 62(2): 117-166.). Some species are thought to be oligolecticoligolectic:
the term used to describe bees that specialize on a narrow range of pollen sources, generally a specific plant genus
on flowers within some of these plant families (Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.).

Nesting behavior

Megachile (Megachiloides) nest in pre-existing cavities. Nest cells are comprised of small, circular pieces of cut leaves (Williams et al. 1986Williams et al. 1986:
Williams, H.J., M.R. Strand, G.W. Elzen, S.B. Vinson, and S.J. Merritt. 1986. Nesting behavior, nest architecture, and use of Dufourrsquo;s gland lipids in nest provisioning by Megachile integra and M. mendica mendica (Hymenoptera: Megachilidae). Journal of the Kansas Entomological Society 59: 588-597.; Krombein and Norden 1995Krombein and Norden 1995:
Krombein, K.V. and B.B. Norden. 1995. Notes on the behavior and taxonomy of Megachile ( Xeromegachile ) brimleyi Mitchell and its probable cleptoparasite, Coelioxys ( Xerocoelioxys ) galactiae Mitchell (Hymenoptera: Megachilidae). Proceedings of the Entomological Society of Washington 97: 86ndash;89.).

Diversity

Megachile (Megachiloides) is one the most diverse subgenera of Megachile in North America with approximately 60 described species (Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.; Sheffield 2013Sheffield 2013:
Sheffield, C.S. 2013. A new species of Megachile Latreille subgenus Megachiloides (Hymenoptera, Megachilidae). ZooKeys 283: 43-58.).

Known invasives

There are no known invasives.

Distribution

Megachile (Megachiloides) ranges from southern Canada to northern Mexico where they primarily occur in xericxeric:
a very dry habitat
areas (Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.; 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.).

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

References

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.

Krombein, K.V. and B.B. Norden. 1995. Notes of the behavior and taxonomy of Megachile (Xeromegachile) brimleyi Mitchell and its probable cleptoparasitecleptoparasite:
bees that lay their eggs in the nest cells of bees in other genera. Their larvae depend on the pollen provided by their host. Since cleptoparasitic bees don't provision their own nests, and instead depend on the pollen collected by their host, the females lack pollen collecting hairs. This often gives them a wasp-like appearance.
, Coelioxys (Xerocoelioxys) galactiae Mitchell (Hymenoptera: Megachilidae). Proceedings of the Entomological Society of Washington 97: 86-89.

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

Mitchell, T.B. 1933. 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 I. Classification and descriptions of new species (Hymenoptera: Megachilidae). Transactions of the American Entomological Society 59(4): 295-361.

Mitchell, T.B. 1936. 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 IV. Taxonomy of subgenera Xanthosarus, Phaenosarus, Megachiloides and Derotropis (Hymenoptera: Megachilidae). Transactions of the American Entomological Society 62(2): 117-166.

Sheffield, C.S. 2013. A new species of Megachile Latreille subgenus Megachiloides (Hymenoptera, Megachilidae). ZooKeys 283: 43-58.

Williams, H.J., M.R. Strand, G.W. Elzen, S.B. Vinson, and S.J. Merritt. 1986. Nesting behavior, nest architecture, and use of Dufour’s gland lipids in nest provisioning by Megachile integra and M. mendica mendica (Hymenoptera: Megachilidae). Journal of the Kansas Entomological Society 59: 588-597.