Cannings, R.A. (1999): The systematics of Lasiopogon Loew (Diptera: Asilidae). PhD thesis, Department of Environmental Biology, University of Guelph, Guelph, Canada. Vol. 1 (text and tables), 293 pp; Vol. 2 (figures), 409 pp).

The abstract, for your information, is below:



Robert Alexander Cannings
University of Guelph, 1999
Prof. S.A. Marshall

This thesis is an investigation of the phylogenetic relationships in the robber fly (Diptera: Asilidae) genus Lasiopogon Loew. Although 118 species -- 49 of them undescribed -- are recognized, only the derived L. opaculus section is revised. It consists of 29 species, 14 of which are newly described: L. apache, L. appalachensis, L. chrysotus, L. coconino, L. and L. woodorum. Three names are synonomized: L. aridus Cole & Wilcox = L. quadrivittatus (Jones); L. atripennis Cole & Wilcox = L. cinereus Cole; L. carolinensis Cole & Wilcox = L. opaculus Loew. All species in the opaculus section are described and illustrated and each has its geographical distribution mapped. Identification keys are provided for all Nearctic and East Palaearctic species.
      The morphology of Lasiopogon is detailed; special attention is paid to the male and female genitalia, which have been little used in previous taxonomic works. For the first time, the gonostylus, phallus, subepandrial sclerite, basal epandrial sclerite and spermathecae are considered important structures in the taxonomy of the genus.
      The placement of Lasiopogon in the Stichopogoninae is upheld; it is considered the sister group to the remainder of the subfamily. The possibility that the Stichopogoninae is linked to the Stenopogoninae through the australasian genus Bathypogon is explored.
      Lasiopogon consists of two main clades: the cinctus clade is predominantly West Palaearctic; the bivittatus clade is mainly Nearctic. The opaculus section, the main object of this study, is a monophyletic, derived lineage in the bivittatus clade. The younger clades of the opaculus section live in the East Palaearctic.
      A biogeographic hypothesis of the history of Lasiopogon suggests that Lasiopogon may have originated in Laurasia as early as the late Jurassic, although the phylogeny of the modern fauna correlates best with geographical events beginning in the Tertiary. The cinctus and bivittatus clades perhaps diverged at the onset of Oligocene climatic cooling. In the Miocene, populations of the opaculus section were continuous across Beringia and into Asia. Almost all the extant East Asian species groups originated at that time. One species, L. hinei, recolonized North America in the Pleistocene.

Dr. Robert A. Cannings, R.P.Bio.
Royal British Columbia Museum
675 Belleville Street
Victoria, B.C., Canada V8W 9W2
Phone (250) 356-8242; Fax (250) 387-0534

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