Pseudomegachile

Taxonomy

Family: Megachilidae
Subfamily: Megachilinae
Tribe: Megachilini
Genus: Pseudomegachile Friese, 1898
Common name: none

Overview

Pseudomegachile are a morphologically diverse and variable subgenus with white, grey, yellow, red, or black hair throughout their bodies (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 10–22 mm (Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.). Pseudomegachile were previously recognized as a subgenus of Megachile but were raised to genus level by Gonzalez et al. 2019Gonzalez et al. 2019:
Gonzalez, V.H., G.T. Gustafson, and M.S. Engel. 2019. Morphological phylogeny of Megachilini and the evolution of leaf-cutter behavior in bees (Hymenoptera: Megachilidae). Journal of Melittology (85): 1-123..

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.; 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.; 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 clypeusclypeus:
  a section of the face below the antennae, demarcated by the epistomal sutures
  is truncatetruncate:
  ending abruptly, or squared off
  or sometimes crenulatecrenulate:
  having a finely scalloped or notched outline or edge
  .
• Female mandiblemandible:
  bee teeth, so to speak, usually crossed and folded in front of the mouth
  is elongate with 3–6 teeth.
• Female mandibularmandibular:
  near the mandible
  ridges are smooth and shiny.
• Male front coxacoxa:
  the basal segment of the leg
  with a spine.
• Male mandiblemandible:
  bee teeth, so to speak, usually crossed and folded in front of the mouth
  four-toothed.
• Male 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
  less sclerotizedsclerotized:
  hardened by the formation of sclerotin, specifically the exoskeleton of an insect
  than 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
  .
• 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 strongly 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
  with long spine medially.

May be confused with

Pseudomegachile has many species that are similar in size and coloration to Callomegachile. Female Pseudomegachile can be differentiated from Callomegachile by their shorter mandibles with smooth, shiny ridges of their mandibules. Male Pseudomegachile can be differentiated by the denticulatedenticulate:
a small tooth-like projection
preapical carinacarina:
a clearly defined ridge or keel, not necessarily high or acute; usually appears on bees as simply a raised line
on 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
, which sometimes has 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
(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

Pseudomegachile are generalists which have been observed visiting species within Asteraceae, Acanthaceae, Fabaceae, Lamiaceae, Papilionaceae, Pedaliaceae, and Plantaginaceae (Banaszak 1976Banaszak 1976:
Banaszak, J. 1976. Apoidea (Hymenoptera) of botanical garden in Paznan, Badania Fizjograficzne Nad Polska Zachodnia. Zoologia 32: 1-85.; Gogala 1991Gogala 1991:
Gogala, A. 1991. Contribution to the knowledge of the bee fauna of Slovenia (Hymenoptera: Apidae). Scopolia 25: 1-33.; Özbek and Zanden 1994Ouml;zbek and Zanden 1994:
Ouml;zbek, H. and G. van der Zanden. 1994. A preliminary review of the Megachilidae of Turkey Part IV. Megachilini and Lithurgini (Hymenoptera: Apoidea). Tuuml;rkiye Entomoloji Dergisi 18: 157-174., Karunaratne et al. 2005Karunaratne et al. 2005:
Karunaratne, W.A.I.P., J.P. Edirisinghe, and C.S. Gunatilleke. 2005. Floral relationships of bees in selected areas of Sri Lanka. Ceylon Journal of Science 34: 27-45.; Gikungu 2006Gikungu 2006:
Gikungu, M.W. 2006. Bee diversity and some aspects of their ecological interactions with plants in a successional tropical community. Apidologie 40(3): 355-366.).

Nesting behavior

Pseudomegachile have been observed nesting in pre-existing cavities in wood, cane, reeds, and soil, as well as in cracks in buildings and in abandoned thread-waisted wasp (Sphecidae) nests (Gupta et al. 2003Gupta et al. 2003:
Gupta, R.K., R.K. Naval, and S.K. Charan. 2003. Nesting biology of the solitary bee, Megachile (Pseudomegachile) creusa Bingham (Hymenoptera, Megachilidae). Mellifera 3(5): 43-50.; Raw 2007Raw 2007:
Raw, A. 2007. An annotated catalogue of the leafcutter and mason bees (genus Megachile ) of the Neotropics. Zootaxa 1601: 1-127.; Gonzalez et al. 2019Gonzalez et al. 2019:
Gonzalez, V.H., G.T. Gustafson, and M.S. Engel. 2019. Morphological phylogeny of Megachilini and the evolution of leaf-cutter behavior in bees (Hymenoptera: Megachilidae). Journal of Melittology (85): 1-123.). Although they are solitary bees, at least one species (Pseudomegachile flavipes) has been reported nesting in aggregations of 200 nests in Egypt (Gupta et al. 2003Gupta et al. 2003:
Gupta, R.K., R.K. Naval, and S.K. Charan. 2003. Nesting biology of the solitary bee, Megachile (Pseudomegachile) creusa Bingham (Hymenoptera, Megachilidae). Mellifera 3(5): 43-50.). These bees build their nests using resins and mud mixed with oral secretions (Gupta et al. 2003Gupta et al. 2003:
Gupta, R.K., R.K. Naval, and S.K. Charan. 2003. Nesting biology of the solitary bee, Megachile (Pseudomegachile) creusa Bingham (Hymenoptera, Megachilidae). Mellifera 3(5): 43-50.; 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

Pseudomegachile consists of approximately 80 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 are not native to the U.S., but one species, Pseudomegachile lanata, has been introduced in Florida (Genaro 2008Genaro 2008:
Genaro, J.A. 2008. Origins, composition and distribution of the bees of Cuba (Hymenoptera: Apoidea: Anthophila). Insecta Mundi (0051-0061): 1-16.; Gonzalez et al. 2019Gonzalez et al. 2019:
Gonzalez, V.H., G.T. Gustafson, and M.S. Engel. 2019. Morphological phylogeny of Megachilini and the evolution of leaf-cutter behavior in bees (Hymenoptera: Megachilidae). Journal of Melittology (85): 1-123.).

Known invasives

In the U.S., Pseudomegachile lanata is invasive in the state of Florida and the territory of Puerto Rico (Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.; Genaro 2008Genaro 2008:
Genaro, J.A. 2008. Origins, composition and distribution of the bees of Cuba (Hymenoptera: Apoidea: Anthophila). Insecta Mundi (0051-0061): 1-16.). Outside of the U.S., it is known to be invasive on many of the Caribbean Islands and in several countries in South America, including Colombia, Bolivia, Guyana, and French Guiana (Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.; Gonzalez et al. 2019Gonzalez et al. 2019:
Gonzalez, V.H., G.T. Gustafson, and M.S. Engel. 2019. Morphological phylogeny of Megachilini and the evolution of leaf-cutter behavior in bees (Hymenoptera: Megachilidae). Journal of Melittology (85): 1-123.).

Distribution

Pseudomegachile are native to Europe, Africa, and Asia, although they have been introduced in the Western Hemisphere (Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.; Genaro 2008Genaro 2008:
Genaro, J.A. 2008. Origins, composition and distribution of the bees of Cuba (Hymenoptera: Apoidea: Anthophila). Insecta Mundi (0051-0061): 1-16.; Gonzalez et al. 2019Gonzalez et al. 2019:
Gonzalez, V.H., G.T. Gustafson, and M.S. Engel. 2019. Morphological phylogeny of Megachilini and the evolution of leaf-cutter behavior in bees (Hymenoptera: Megachilidae). Journal of Melittology (85): 1-123.). In Europe, they are most abundant in the Mediterranean region, but can be found as far north as Finland (Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.). In Africa, they are widespread and can be found from the Mediterranean to South Africa, as well as on Madagascar and Réunion islands off the eastern coast. In Asia, they are found from the Mediterranean coast of Southwest Asia to Indonesia and the eastern coast of China (Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.).

Pseudomegachile lanata, a species that is native to India and has spread to Africa, was introduced to the Caribbean Islands during the slave trade (Genaro 2008Genaro 2008:
Genaro, J.A. 2008. Origins, composition and distribution of the bees of Cuba (Hymenoptera: Apoidea: Anthophila). Insecta Mundi (0051-0061): 1-16.). They have since spread to the U.S. (Florida) and South America (Gonzalez et al. 2019Gonzalez et al. 2019:
Gonzalez, V.H., G.T. Gustafson, and M.S. Engel. 2019. Morphological phylogeny of Megachilini and the evolution of leaf-cutter behavior in bees (Hymenoptera: Megachilidae). Journal of Melittology (85): 1-123.).

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

References

Banaszak, J. 1976. Apoidea (Hymenoptera) of botanical garden in Paznan, Badania Fizjograficzne Nad Polska Zachodnia. Zoologia 32: 1-85.

Genaro, J.A. 2008. Origins, composition and distribution of the bees of Cuba (Hymenoptera: Apoidea: Anthophila). Insecta Mundi 2008(0051-0061): 1-16

Gikungu, M.W. 2006. Bee diversity and some aspects of their ecological interactions with plants in a successional tropical community. Apidologie 40(3): 355-366.

Gogala, A. 1991. Contribution to the knowledge of the bee fauna of Slovenia (Hymenoptera: Apidae). Scopolia 25: 1-33.

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.

Gonzalez, V.H., D.A. Guevara, J. Jaramillo-Silva, and R. Ospina. 2019. Discovery of Megachile (Pseudomegachile) lanata (Fabricius, 1775) (Hymenoptera, Megachilidae) in Colombia, an adventive bee species from the Old WorldOld World:
the part of the world that was known before the discovery of the Americas, comprised of Europe, Asia, and Africa; the Eastern Hemisphere
. Check List 15: 45.

Gupta, R.K., R.K. Naval, and S.K. Charan. 2003. Nesting biology of the solitary bee, Megachile (Pseudomegachile) creusa Bingham (Hymenoptera, Megachilidae). Mellifera 3(5): 43-50.

Karunaratne, W.A.I.P., J.P. Edirisinghe, and C.S. Gunatilleke. 2005. Floral relationships of bees in selected areas of Sri Lanka. Ceylon Journal of Science 34: 27-45.

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

Özbek, H. and G. van der Zanden. 1994. A preliminary review of the Megachilidae of Turkey Part IV. Megachilini and Lithurgini (Hymenoptera: Apoidea). Türkiye Entomoloji Dergisi 18: 157-174.

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.

Raw, A. 2007. An annotated catalogue of the leafcutter and mason bees (genus Megachile) of the Neotropics. Zootaxa 1601: 1-127.