Family: Megachilidae
Subfamily: Megachilinae
Tribe: Osmiini
Genus: Osmia Panzer, 1806
Subgenus: Diceratosmia Robertson, 1903
Common name: none
Osmia (Diceratosmia) are metallic blue or green bees with mostly pale pubescencepubescence:
short, fine hair
, including scopal hairs, which can be white, golden, or reddish-golden (Griswold and Rightmyer 2017Griswold and Rightmyer 2017:
Griswold, T. and M.G. Rightmyer. 2017. A revision of the subgenus Osmia (Diceratosmia) , with descriptions of four new species (Hymenoptera: Megachilidae). Zootaxa 4337: 1ndash;37.). They range in body length from 4–8 mm (Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.).
(modified from Griswold and Rightmyer 2017Griswold and Rightmyer 2017:
Griswold, T. and M.G. Rightmyer. 2017. A revision of the subgenus Osmia (Diceratosmia) , with descriptions of four new species (Hymenoptera: Megachilidae). Zootaxa 4337: 1ndash;37., unless otherwise stated)
Osmia (Diceratosmia) may be confused with O. (Pyrosmia) due to similar characters such as carinatecarinate:
having keels or carinae
posterior margin of the 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
, carinatecarinate:
having keels or carinae
hind coxaecoxae:
the basal segment of the leg
in females, short pale pubescencepubescence:
short, fine hair
, and elongate parapsidal lines (Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.). However, these subgenera can be differentiated by the hind coxaecoxae:
the basal segment of the leg
being extremely carinatecarinate:
having keels or carinae
in both sexes of O. (Diceratosmia), whereas it is less carinatecarinate:
having keels or carinae
in male O. (Pyrosmia) (Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.). Additionally, O. (Diceratosmia) lacks a median groove on the 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
, which is present in O. (Pyrosmia) (Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.).
Osmia (Diceratosmia) have been observed visiting Asteraceae, Lamiaceae, Nyctaginaceae, Brassicaceae, Rubiaceae, Fabaceae, Boraginaceae, Cactaceae, Malvaceae, Arecaceae, Anacardiaceae, Plantaginaceae, Portulacaceae, Rhamnaceae, Rosaceae, Salicaceae, Solanaceae, and Zygophyllaceae (Dieringer et al. 1991Dieringer et al. 1991:
Dieringer, G., T.P. Ramamoorthy, and P.T. Lezama. 1991. Floral visitors and their behavior to sympatric Saliva species (Lamiaceae) in Mexico. Acta Botanica Mexicana 13: 75ndash;83.; Griswold and Rightmyer 2017Griswold and Rightmyer 2017:
Griswold, T. and M.G. Rightmyer. 2017. A revision of the subgenus Osmia (Diceratosmia) , with descriptions of four new species (Hymenoptera: Megachilidae). Zootaxa 4337: 1ndash;37.). One species of Diceratosmia, Osmia conjunctoides, was observed visiting Crotalaria pumila (Rightmyer et al. 2011Rightmyer et al. 2011:
Rightmyer, M.G., M. Deyrup, J.S. Ascher, and T. Griswold. 2011. Osmia species (Hymenoptera, Megachilidae) from the southeastern United States with modified facial fairs: taxonomy, host plants, and conservation status. Zookeys 148: 257-278.).
Osmia (Diceratosmia) have been observed nesting in snail shells, beetle burrows, and leaf pulp rolled in the sand (Rau 1937; Linsley 1946Linsley 1946:
Linsley, E.G. 1946. Insect pollinators of alfalfa in California. Journal of Economic Entomology 39: 18ndash;29.; Mitchell 1962Mitchell 1962:
Mitchell, T.B. 1962. Bees of the Eastern United States. Vol. II. North Carolina Agricultural Experiment Station Technical Bulletin 152:1ndash;557.; Krombein 1967Krombein 1967:
Krombein, K.V. 1967. Trap nesting wasp and bees: life histories, nests, and associates. Washington, DC: Smithsonian Press.; Neff and Simpson 1992Neff and Simpson 1992:
Neff, J.L. and B.B. Simpson. 1992. Nest biology of Osmia (Diceratosmia) subfasciata Cresson in central Texas (Hymenoptera: Megachilidae). Pan-Pacific Entomology 68: 15ndash;26.; Griswold and Rightmyer 2017Griswold and Rightmyer 2017:
Griswold, T. and M.G. Rightmyer. 2017. A revision of the subgenus Osmia (Diceratosmia) , with descriptions of four new species (Hymenoptera: Megachilidae). Zootaxa 4337: 1ndash;37.). Osmia (Diceratosmia) is the only Osmia subgenus in the Western Hemisphere that is known to nest in snail shells (Cane et al. 2007Cane et al. 2007:
Cane, J.H., T. Griswold, and F.D. Parker. 2007. Substrates and materials used for nesting by North American Osmia bees (Hymenoptera: Apiformes: Megachilidae). Annals of the Entomological Society of America 100: 350ndash;358.; Griswold and Rightmyer 2017Griswold and Rightmyer 2017:
Griswold, T. and M.G. Rightmyer. 2017. A revision of the subgenus Osmia (Diceratosmia) , with descriptions of four new species (Hymenoptera: Megachilidae). Zootaxa 4337: 1ndash;37.).
Osmia (Diceratosmia) contains eleven species (Griswold and Rightmyer 2017Griswold and Rightmyer 2017:
Griswold, T. and M.G. Rightmyer. 2017. A revision of the subgenus Osmia (Diceratosmia) , with descriptions of four new species (Hymenoptera: Megachilidae). Zootaxa 4337: 1ndash;37.).
There are no known invasives.
Osmia (Diceratosmia) is endemic to North America and can be found from Costa Rica to southeastern Canada, with most species occurring in southern U.S. and Mexico (Griswold and Rightmyer 2017Griswold and Rightmyer 2017:
Griswold, T. and M.G. Rightmyer. 2017. A revision of the subgenus Osmia (Diceratosmia) , with descriptions of four new species (Hymenoptera: Megachilidae). Zootaxa 4337: 1ndash;37.).
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Cane, J.H., T. Griswold, and F.D. Parker. 2007. Substrates and materials used for nesting by North American Osmia bees (Hymenoptera: Apiformes: Megachilidae). Annals of the Entomological Society of America 100: 350–358.
Dieringer, G., T.P. Ramamoorthy, and P.T. Lezama. 1991. Floral visitors and their behavior to sympatricsympatric:
overlapping geographic distribution
Saliva species (Lamiaceae) in Mexico. Acta Botanica Mexicana 13: 75-83.
Griswold, T. and M.G. Rightmyer. 2017. A revision of the subgenus Osmia (Diceratosmia), with descriptions of four new species (Hymenoptera: Megachilidae). Zootaxa 4337: 1-37.
Krombein, K.V. 1967. Trap nesting wasps and bees: life histories, nests, and associates. Smithsonian Press, Washington, DC.
Linsley, E.G. 1946. Insect pollinators of alfalfa in California. Journal of Economic Entomology 39: 18-29.
Michener, C.D. 2007. The Bees of the World. 2nd ed. Johns Hopkins University Press, Baltimore and London, 953 pp.
Mitchell, T.B. 1962. Bees of the eastern United States, 2ed. North Carolina Agricultural Experiment Station Technical Bulletin 152.
Neff, J.L. and B.B. Simpson. 1992. Nest biology of Osmia (Diceratosmia) subfasciata Cresson in central Texas (Hymenoptera: Megachilidae). Pan-Pacific Entomology 68: 15-26.
Rightmyer, M.G., M. Deyrup, J.S. Ascher, and T. Griswold. 2011. Osmia species (Hymenoptera, Megachilidae) from the southeastern United States with modified facial fairs: taxonomy, host plants, and conservation status. Zookeys 148: 257-278.