Heterogyna

Heterogyna
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Suborder:	Apocrita
Superfamily:	Apoidea
Family:	Heterogynaidae
Genus:	Heterogyna Nagy, 1969
Species
Heterogyna botswana Heterogyna fantsilotra Heterogyna kugleri Heterogyna madecassa Heterogyna nocticola Heterogyna polita Heterogyna protea Heterogyna ravenala

The Heterogynaidae are a minor family (only eight described species in a single genus, Heterogyna) of small spheciform wasps occurring in Madagascar, Botswana, Turkmenistan, Oman, the United Arab Emirates, and the Eastern Mediterranean area. The majority are dark in color and range in size from approximately 1.5 to 5.0 mm. Most specimens have been collected in arid climates, but one species from Madagascar is known to occur in a humid forest habitat. Although males have functional wings, heterogynaid females are typically brachypterous, a trait which is unique among spheciform wasps. Wing venation is reduced in both sexes. All species are diurnal, with the exception of H. nocticola. Other aspects of their biology are completely unknown, but details of their morphology have prompted researchers to hypothesize that they may be non-fossorial parasitoids adapted to hunt in tight spaces, such as under tree bark. This is speculative and has not yet been confirmed by actual observations of behavior. It is also possible that modifications of the female metasomal tergum VI and gonostyli may represent a unique prey transport mechanism, but this is also unconfirmed.

The Heterogynaidae are generally considered the sister taxon to the remainder of the Apoidea. However, the results of recent studies utilizing molecular characters suggest that this hypothesis may be incorrect. A preliminary study by Ohl and Bleidorn (2006) suggested that the heterogynaids arose from within the Crabronidae, but a later study by Debevec et al. (2012) showed very weak support for this hypothesis. Their results much more strongly suggested that the Heterogynaidae are the sister taxon to a clade composed of the Sphecidae, the Crabronidae, and the Anthophila. Monophyly of the family is strongly supported.

References

• Day, M.C. (1984) "The enigmatic genus Heterogyna Nagy (Hymenoptera: Sphecidae; Heterogyninae)". Systematic Entomology, 9, 293-307.
• Debevec, A.H., Cardinal, S., Danforth, B.N. (2012) "Identifying the sister group to the bees: a molecular phylogeny of Aculeata with an emphasis on the superfamily Apoidea". Zoologica Scripta, 41 (5): 527-535.
• Goulet, H., Huber, J.T. (1993) Hymenoptera of the World. Agriculture Canada Research Branch, publication 1894/E. 668pp.
• Ohl, M. (2008) Order Hymenoptera, family Heterogynaidae, pp.403-406 in: A. van Harten (editor). Arthropod Fauna of the UAE, Volume 1. Dar el Ummah, Abu Dhabi. 754 pp.
• Ohl, M. & Bleidorn, C. (2006) "The phylogenetic position of the enigmatic wasp family Heterogynaidae based on molecular data, with a new description of a new, nocturnal species (Hymenoptera: Apoidea)". Systematic Entomology, 31, 321-337.