Ragadidae

Ragadidae
Ragas unica
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Diptera
Suborder:	Brachycera
Infraorder:	Asilomorpha
Superfamily:	Empidoidea
Family:	Ragadidae Sinclair, 2016
Subfamilies
Iteaphilinae Ragadinae

Ragadidae is a family of true flies in the superfamily Empidoidea. It was formerly considered a lower taxon, but was published as a new subfamily within Empididae in 2016. Since then, it has been classified as the sister group to Empididae, and has been elevated to family level based on the genetic differences which separate it from Empididae.

Description

Photograph of right wing of a species within Ragadidae, Ragas unica

Ragadidae are similar to Empididae and Atelestidae in the sense that their genitalia have symmetrical and straight terminalia. In their wings, the point of origin of the R_s vein is located at a distance from the humeral crossvein (h) as long as, or longer than, h. There is also a circumambient costa in the wing, which distinguishes Ragadidae from Atelestidae. Furthermore, the prosternum being separated from the proepisternum sets Ragadidae aside from Empididae—this is true for all except one genera (Hydropeza spp.), which can instead be characterized through its recurved labrum. In Empididae, this labrum is straight.

Systematics

Ragadidae consists of two subfamilies, Iteaphilinae and Ragadinae, in which 7 genera are included in total: Dipsomyia, Hormopeza, Hydropeza, Ragas, Zanclotus, Anthepiscopus and Iteaphila.

Based on the most recent phylogenetic studies, the relationship between Ragadidae and other members of Empidoidea is as follows. The placement of Ragadidae is emphasized in bold formatting.

Atelestidae	Atelestinae Nemedininae
	Hybotidae Bicellariinae Hybotinae Oedaleinae Ocydromiinae Trichininae Tachydromiinae Tachydromiini Symballaphthalmini Drapetini Dolichopodidae Ragadidae Iteaphilinae Ragadinae Empididae Clinocerinae Brachystomatinae Brachystomatini Ceratomerini Trichopezini Empidinae Chelipodini Empidini Hemerodromiini Hilarini

References

• Sinclair, B. J. (2016): Revision of the Australian species of Hydropeza Sinclair (Diptera: Empididae: Ragadinae subfam. nov.). Records of the Australian Museum 68: 1–22. doi:10.3853/j.2201-4349.68.2016.1657
• Wahlberg, E. & Johanson, K.A. (2018): Molecular phylogenetics reveals novel relationships within Empidoidea (Diptera). Systematic Entomology 43(4): 619–636. doi:10.1111/syen.12297