Radoszkowskiana

Taxonomy

Family: Megachilidae
Subfamily: Megachilinae
Tribe: Megachilini
Genus: Radoszkowskiana Popov, 1955
Subgenera: none
Common name: none

Overview

Radoszkowskiana are cleptoparasites that range in body length from 10–13 mm. Females have a red abdomen, while males have a black abdomen (Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.). Female’s second abdominal segment is the widest and tapers posteriorly (Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.).

Diversity

Radoszkowskiana consists of four species (Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.); none are known to occur in the U.S. or Canada.

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.)

• Arolia absent.
• Axilla axilla:
  the triangular or rounded point on the thorax where thoracic muscles meet the forewing of an insect
  rounded, with a notch in between the posterior axillaaxilla:
  the triangular or rounded point on the thorax where thoracic muscles meet the forewing of an insect
  and scutellar margins.
• Preoccipital carinacarina:
  a clearly defined ridge or keel, not necessarily high or acute; usually appears on bees as simply a raised line
  absent medially but present on the side of the head.
• Pronotal lobe pronotal lobe:
  a part of the pronotum located dorsally on the posterior margin of the pronotum and overlaps the anterior thoracic spiracle
  lamellatelamellate:
  thin, plate-like, often somewhat translucent structure
  extending posterolaterally as a flat spine.
• Stigma stigma:
  a pigmented/ thickened spot on the costal margin of the forewing, usually at the end of the radius(Greek, stigma= mark)
  twice as long as broad or more.
• Males have four exposed abdominal 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
  .
• Males 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
  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
  is strong, transverse, and denticulatedenticulate:
  a small tooth-like projection
  .
• Females lack a 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
  is longer than it is broad.
• 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
  is rounded and extends beyond 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
  .

May be confused with

Radoszkowskiana may be confused with species in the genus Coelioxys due to tapering of the abdomen after the second segment in females, lack of 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
, and presence of preoccipital carinacarina:
a clearly defined ridge or keel, not necessarily high or acute; usually appears on bees as simply a raised line
on the side of the head (Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.). Radoszkowskiana males may also be confused with Megachile due to the blunt shape of 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
, and rounded axillaaxilla:
the triangular or rounded point on the thorax where thoracic muscles meet the forewing of an insect
(Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.). Radoszkowskiana can be differentiated from these two genera based on the combination of distinguishing characteristics listed above. In addition, larval Radoszkowskiana can be differentiated from Coelioxys by the curvature of the first instar’s mandibles: Radoszkowskiana curve orally, while Coelioxys bend caudally (Rozen and Kamel 2008Rozen and Kamel 2008:
Rozen, J.G., Jr. and S.M. Kamel. 2008. Hospicidal behavior of the cleptoparasitic bee Coelioxys ( Allocoelioxys ) coturnix , including descriptions of its larval instars (Hymenoptera: Megachilidae). American Museum Novitates 3636: 1ndash;15.). Further, Radoszkowskiana can be differentiated from Megachile by the lack of ventralventral:
of, on, or relating to the underside of an animal, or segment of an animal
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
(Ozbek and Schwarz 2016).

Known invasives

There are no known invasives.

Host associations

Radoszkowskiana is a group of cleptoparasiticcleptoparasitic:
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.
bees whose only known host is Megachile nigripes (Rozen and Kamel 2007Rozen and Kamel 2007:
Rozen Jr., J.G. and S.M. Kamel. 2007. Investigations on the biologies and immature stages of the cleptoparasitic bee genera Radoszkowskiana and Coelioxys and their Megachile hosts (Hymenoptera: Apoidea: Megachilidae: Megachilini). American Museum Novitates 3573: 1ndash;43.). Radoszkowskiana feed on their own chorion and the host’s yolk as first instar larvaelarvae:
active immature form of an insect, especially one that differs greatly from the adult and forms the stage between egg and pupa
(Rozen and Kamel 2007Rozen and Kamel 2007:
Rozen Jr., J.G. and S.M. Kamel. 2007. Investigations on the biologies and immature stages of the cleptoparasitic bee genera Radoszkowskiana and Coelioxys and their Megachile hosts (Hymenoptera: Apoidea: Megachilidae: Megachilini). American Museum Novitates 3573: 1ndash;43.).

Nesting behavior

Female R. rufiventris lay their eggs in host nests of Megachile nigripes by either opening closed nests or, more likely, by entering the nest when the host is away (Rozen and Kamel 2007Rozen and Kamel 2007:
Rozen Jr., J.G. and S.M. Kamel. 2007. Investigations on the biologies and immature stages of the cleptoparasitic bee genera Radoszkowskiana and Coelioxys and their Megachile hosts (Hymenoptera: Apoidea: Megachilidae: Megachilini). American Museum Novitates 3573: 1ndash;43.). Once in the nest, the female R. rufiventris lays an egg on top of the host egg, which is known to develop more slowly (Rozen and Kamel 2008Rozen and Kamel 2008:
Rozen, J.G., Jr. and S.M. Kamel. 2008. Hospicidal behavior of the cleptoparasitic bee Coelioxys ( Allocoelioxys ) coturnix , including descriptions of its larval instars (Hymenoptera: Megachilidae). American Museum Novitates 3636: 1ndash;15.). Once the 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.
’s egg hatches, the larvalarva:
active immature form of an insect, especially one that differs greatly from the adult and forms the stage between egg and pupa
kills the embryonic host by biting it with short, fang-like mandibles and then consumes its own chorion while staying on top of the dead host egg (Rozen and Kamel 2008Rozen and Kamel 2008:
Rozen, J.G., Jr. and S.M. Kamel. 2008. Hospicidal behavior of the cleptoparasitic bee Coelioxys ( Allocoelioxys ) coturnix , including descriptions of its larval instars (Hymenoptera: Megachilidae). American Museum Novitates 3636: 1ndash;15.).

Distribution

Radoszkowskiana are distributed from Algeria to the Trans-Caspian region (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

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

Ozbek, H. and M. Schwarz. 2016. Distribution data of the kleptoparasitickleptoparasitic:
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.
bees in Turkey: part 2. Genera Coelioxys and Radoszkowskiana (Hymenoptera: Megachilidae: Megachilinae) with their checklist. Linzer Biol. Beitr. 48:1753-1771

Rozen Jr., J.G. and S.M. Kamel. 2007. Investigations on the biologies and immature stages of the cleptoparasiticcleptoparasitic:
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.
bee genera Radoszkowskiana and Coelioxys and their Megachile hosts (Hymenoptera: Apoidea: Megachilidae: Megachilini). American Museum Novitates 3573:1-43.

Rozen Jr., J.G. and S.M. Kamel. 2008. Hospicidalhospicidal:
the early instars of clepoparasitic bees, which have been oviposited into complete brood cells of another species. When the early instars develop, they kill off the developing individual that was originally occupying the brood cell.
behavior of the cleptoparasiticcleptoparasitic:
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.
bee Coelioxys (Allocoelioxys) coturnix, including descriptions of its larval instars (Hymenoptera: Megachilidae). American Museum Novitates 3636:1-15.