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Family Mydidae - Mydas Flies

Phyllomydas parvulus - female Need ID please... - Mydas clavatus Robber Fly - Mydas clavatus Delhi Sands Flower-loving Fly - Rhaphiomidas terminatus - female large pollinator - Rhaphiomidas aitkeni - male Mydas flies - Mydas clavatus - male - female Blue-Black Mydas Fly - Phyllomydas phyllocerus - male undescribed species - Rhaphiomidas - male
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Diptera (Flies)
No Taxon (Orthorrhapha)
Superfamily Asiloidea
Family Mydidae (Mydas Flies)
Synonyms and other taxonomic changes
Explanation of Names
Mydidae Latreille 1809
see Mydas
~80 spp. in 9 genera of 4 subfamilies in our area(1), ~500 spp. in 66 genera of 11 subfamilies worldwide(1)(2)
  Subfamily Ectyphinae
      Heteromydas: 1 spp.
      Opomydas: 2 spp.
  Subfamily Leptomydinae
      Nemomydas: 12 spp.
      Pseudonomoneura: 7 spp.
  Subfamily Mydinae
      Messiasia: 2 spp.
      Mydas: 26 spp.
      Phyllomydas: 7 spp.
      Stratiomydas: 4? spp.
  Subfamily Rhaphiomidinae
      Rhaphiomidas: 23 spp.
9-60 mm(3) (our spp. to ~30 mm?); neotropical Gauromydas heros is world's largest dipteran(1)
Large flies, often wasp mimics. Have prominent, clubbed antennae and distinctive wing venation:

Artigas & Papavero (1990) contains a key to the genera of Mydidae in the Americas. Note that the majority of genera treated in Artigas & Papavero are restricted to meso- and South America and thus do not occur in our area...but those that do are listed in the "Numbers" section above.
Worldwide, primarily in tropical and subtropical regions (most diverse in Subsaharan, esp. so. Africa but poorly represented in the Oriental Region), with some representation in temperate climes(1); in our area, most spp. have restricted distribution, mostly in sw. US(3). Mydas clavatus is widespread, largely eastern.
Primarily in arid environments, although quite a few species occur in forests(1), e.g., Mydas clavatus.
Life Cycle
Life cycle details not known for many groups; generally, larvae live in decaying wood or soil; some known to prey on beetle larvae(3).
Larva and pupa of Mydas clavatus:
Batesian mimicry of large spider wasps (Pompilidae: Pepsis, Hemipepsis) by Mydas flies is discussed in(4).
See Also
Asilidae - Robber Flies (Mydas flies have prominent clubbed antennae, different wing venation).
Print References
Artigas, J. N, & N. Papavero (1990). "Studies on Mydidae (Diptera): V. Phylogenetic and biogeographic notes, key to the American genera and illustrations of spermathecae". Gayana Zool. 54(3-4): 87-116 (Full Text)
Hardy, D. E. (1944). New Asilidae and Mydaidae (Diptera) in the Snow Collection. Canad. Ent. 76: 226-230.
Hardy, D. E. (1950). "The Nearctic Nomoneura and Nemomydas (Diptera:Mydaidae)". Wasmann Journal of Biology 8: 9-37. (Full Text)
Johnson, C. W. (1926). “A revision of some of the North American species of Mydaidae”, Proceedings of the Boston Society of Natural History, vol. 38, pp. 131–145
Osten-Saken, C. R. (1886) "Family Midaidae" in: Biologia Centrali-Americana, Insecta. Diptera. Vol. I, edited by F. D. Godman and Salvin, O., London: Porter, 1901, pp. 68-73. (Full text)
Wilcox, J., Papavero, N. (1971). "The American genera of Mydidae (Diptera) with the description of three new genera and two new species". Arquivos Zoologica São Paulo. 21 (2): 41–119 (Full Text)
Wilcox, J., Papavero, N. & Pimentel, T. (1989). Studies of Mydidae (Diptera). IVb. Mydas and allies in the Americas (Mydinae, Mydini). Museu Paraense "Emilo Goeldi", Coleção Emilie Snethlage, Belém, Brazil. 139 pp.
Works Cited
1.Dikow T. (2001–2014) Asiloid Flies web-site
2.Order Diptera Linnaeus, 1758. In: Zhang Z.-Q. (ed.) Animal biodiversity: An outline of higher-level classification...
Pape T., Blagoderov V., Mostovski M.B. 2011. Zootaxa 3148: 222–229.
3.American Insects: A Handbook of the Insects of America North of Mexico
Ross H. Arnett. 2000. CRC Press.
4.Sonoran Desert Summer
John Alcock, Marilyn Hoff Stewart. 1994. University of Arizona Press.