Thaumatosoma

Taxonomy

Family: Megachilidae
Subfamily: Megachilinae
Tribe: Megachilini
Genus: Thaumatosoma Smith, 1865
Common name: none

Overview

Thaumatosoma are robust bees that range in body length from 9–12 mm (Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.). Thaumatosoma was elevated from a subgenus of Megachile to genus status by Gonzalez et al. (2019).

Diagnostic characteristics

(modified from King and Exley 1985King and Exley 1985:
King, J. and E.M. Exley. 1985. A revision of Chalicodoma (Chalicodomoides) Michener (Hymenoptera: Megachilidae). Journal of the Australian Entomological Society 24: 187-204; Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.)

• Female mandiblemandible:
  bee teeth, so to speak, usually crossed and folded in front of the mouth
  is long and bidentatebidentate:
  having two teeth
  .
• 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 round basolateral shoulders and concave laterallateral:
  relating, pertaining, or attached to the side
  margins.
• Male clypeusclypeus:
  a section of the face below the antennae, demarcated by the epistomal sutures
  with long, coarse bristles medially.
• Male flagellumflagellum:
  any segment of the antenna past the scape and pedicel
  attenuate.
• Male antenna modified; the scapescape:
  the basal, and usually the longest, segment of the antennae
  is distinctly swollen and the last two flagellomeres are flattened and strongly expanded.
• Male hind tibiatibia:
  the segment of the leg, between the femur and the tarsus
  with one tibial spurtibial spur:
  apical projection(s) often found at the apex of the tibia
  instead of two.

May be confused with

Thaumatosoma may be confused with bees within the genus Hackeriapis due to the shared characteristics of postgradular grooves on T2–T3 and expanded apicalapical:
near or at the apex or end of any structure
flagellar segments in some Hackeriapis males (Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.). Female Thaumatosoma can be differentiated from Hackeriapis by their bidentatebidentate:
having two teeth
mandible and 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 round basolateral shoulders (Michener 2007Michener 2007:
Michener, C.D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.). Male Thaumatosoma can be differentiated from Hackeriapis by the uniquely swollen scapescape:
the basal, and usually the longest, segment of the antennae
, expanded apicalapical:
near or at the apex or end of any structure
flagella, and long, coarse bristles in the center of the clypeusclypeus:
a section of the face below the antennae, demarcated by the epistomal sutures
(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

Thaumatosoma are known to visit flowers of plants in the families Goodeniaceae and Myoporaceae (King and Exley 1985King and Exley 1985:
King, J. and E.M. Exley. 1985. A revision of Chalicodoma (Chalicodomoides) Michener (Hymenoptera: Megachilidae). Journal of the Australian Entomological Society 24: 187-204).

Nesting behavior

Nesting behavior is unknown.

Diversity

Thaumatosoma consists of two 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.

Known invasives

There are no known invasives. 

Distribution

Thaumatosoma occurs throughout the southern third of Australia. They are found predominantly along the western coast as well as inland areas with desert-like conditions (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

King, J. and E.M Exley. 1985. A reinstatement and revision of the genus Thaumatosoma Smith (Apoidea: Megachilidae). Australian Journal of Entomology 24(2): 87-92.

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.

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