Megachile (Sayapis)

Taxonomy

Family: Megachilidae
Subfamily: Megachilinae
Tribe: Megachilini
Genus: Megachile Latreille, 1802
Subgenus: Sayapis Titus, 1906
Common name: none

Overview

Megachile (Sayapis) are slender, narrow, parallel-sided bees with black integumentintegument:
a tough, protective outer layer
on the head, thorax, and abdomen and pale apicalapical:
near or at the apex or end of any structure
bands 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
(Mitchell 1937bMitchell 1937b:
Mitchell, T.B. 1937. A revision of the genus Megachile in the Nearctic region. Part VIII. Taxonomy of the subgenus Chelostomoides, addenda and index (Hymenoptera: Megachilidae). Transactions of the American Entomological Society 63: 381-421.; 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 10–18 mm (Mitchell 1937bMitchell 1937b:
Mitchell, T.B. 1937. A revision of the genus Megachile in the Nearctic region. Part VIII. Taxonomy of the subgenus Chelostomoides, addenda and index (Hymenoptera: Megachilidae). Transactions of the American Entomological Society 63: 381-421.).

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.)

• Tarsal claws usually with a sharp basalbasal:
  originating at the foundation of a structure
  tooth.
• Female mandiblemandible:
  bee teeth, so to speak, usually crossed and folded in front of the mouth
  is four-toothed with or without an incomplete cutting edge in the second interspace and no cutting edge in the third interspace.
• 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
  with a projecting apicalapical:
  near or at the apex or end of any structure
  margin, which causes it to appear distally concave in profile.
• Male abdomen has four exposed 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
  in repose.
• Male front coxacoxa:
  the basal segment of the leg
  with a spine present.
• Male front tarsitarsi:
  the group of segments at the end of the leg following the tibia
  , usually light-colored, expanded, or highly modified.
• Male mandiblemandible:
  bee teeth, so to speak, usually crossed and folded in front of the mouth
  is three-toothed with a large, 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
  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
  emarginate medially.
• 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
  apicalapical:
  near or at the apex or end of any structure
  margin with laterallateral:
  relating, pertaining, or attached to the side
  teeth.

May be confused with

Megachile (Sayapis) may be superficially confused with bees within the subgenus Megachile (Chelostomoides) as both have narrow, parallel-sided abdomens (Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.). Male Megachile (Sayapis) can be differentiated from Megachile (Chelostomoides) by the four exposed 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
in repose (Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.). Female Megachile (Sayapis) can be differentiated from Megachile (Chelostomoides) by the mandiblemandible:
bee teeth, so to speak, usually crossed and folded in front of the mouth
with a single cutting edge in the second interspace and nowhere else (Mitchell 1937bMitchell 1937b:
Mitchell, T.B. 1937. A revision of the genus Megachile in the Nearctic region. Part VIII. Taxonomy of the subgenus Chelostomoides, addenda and index (Hymenoptera: Megachilidae). Transactions of the American Entomological Society 63: 381-421.; 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 (Sayapis) are polylecticpolylectic:
bees that collect pollen from the flowers of a variety of unrelated plants
and have been recorded visiting multiple plant families, including Acanthaceae, Amaranthaceae, Apocynaceae, Aquifoliaceae, Arecaceae, Asteraceae, Boraginaceae, Cactaceae, Cleomaceae, Euphorbiaceae, Fabaceae, Lamiaceae, Lythraceae, Malvaceae, Olacaceae, Onagraceae, Plantaginaceae, Polemoniaceae, Polygonaceae, Rhamnaceae, Rubiaceae, Tamaricaceae, Verbenaceae, and Zygophyllaceae (Deyrup et al. 2002Deyrup et al. 2002:
Deyrup, M., Edirisinghe, J. and Norden, B. 2002. The diversity and floral hosts of bees at the Archbold Biological Station, Florida (Hymenoptera: Apoidea). Insecta Mundi 16: 87-120, 544.; Raw 2007Raw 2007:
Raw, A. 2007. An annotated catalogue of the leafcutter and mason bees (genus Megachile ) of the Neotropics. Zootaxa 1601: 1-127.).

Nesting behavior

Megachile (Sayapis) typically create nests using cut leaves and soil (mud or sand) in pre-existing cavities, although nesting behavior varies by species (Raw 2007Raw 2007:
Raw, A. 2007. An annotated catalogue of the leafcutter and mason bees (genus Megachile ) of the Neotropics. Zootaxa 1601: 1-127.). These bees have been observed nesting in a variety of both natural and man-made locations: Megachile zaptlana has been observed nesting in abandoned beetle burrows, M. cylindrica in Peruvian peppertree (Schinus polygamus) galls, M. policaris in adobe walls, and M. inimica in mesquite trees and fence posts (Raw 2007Raw 2007:
Raw, A. 2007. An annotated catalogue of the leafcutter and mason bees (genus Megachile ) of the Neotropics. Zootaxa 1601: 1-127.).

Diversity

Megachile (Sayapis) consists of 24 species, four of which occur in the U.S. (Raw 2007Raw 2007:
Raw, A. 2007. An annotated catalogue of the leafcutter and mason bees (genus Megachile ) of the Neotropics. Zootaxa 1601: 1-127.; 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 (Sayapis) is native to North and South America, where they range from Canada to Argentina (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=Sayapis&flags=subgenus:

Deyrup, M., J. Edirisinghe, and B. Norden. 2002. The diversity and floral hosts of bees at the Archbold Biological Station, Florida (Hymenoptera: Apoidea). Insecta Mundi 544.

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: 295-361.

Mitchell, T.B. 1937. 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 VII. Taxonomy of the subgenus Sayapis. Transactions of the American Entomological Society 63: 381-421.

Raw, A. 2007. An annotated catalogue of the leafcutter and mason bees (Genus Megachile) of the Neotropics. Zootaxa 1906: 1-127.