The Dixidae (meniscus midges) are a family of aquatic nematoceran flies (Diptera). The larvae live in unpolluted, standing fresh waters, just beneath the surface film, usually amongst marginal aquatic vegetation.[2][3] They are found in all continents except Antarctica.

Dixidae
Temporal range: Early Jurassic–Recent
Dixa nebulosa
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Diptera
Superfamily: Culicoidea
Family: Dixidae
Schiffner, 1868
Genera

Description

edit

For terms see Morphology of Diptera

 
Wing venation

Dixidae are small (body length not more than 5.0 mm) slender gnats with thin legs. Adults are black to yellowish-brown.[4] The head is relatively broad. The antennae are thin and the flagellum has 14 segments. The proboscis is short and thick and the palpi are five-segmented. The thorax is slightly convex. The wing veins are without scales (with scales in the closely related family Culicidae. The subcosta is fused with the costa at the level of the base of Rs or slightly proximal to this. The wing venation exhibits radial, medial, and cubital forks (R 4 branched, M 2 branched, Cu 2 branched). R 2+ 3 is strongly arched, the r–m crossvein is distinct, and the discal cell is absent. The anal vein of the wing is long. The genitalia of the male is inverted at 180° by torsion of segments 5–8.

Evolutionary history

edit

The oldest known fossils of the group come from the Jurassic of Asia, assigned to the extinct genera Syndixa and Eucorethrina, members of modern genera are not known until the Eocene.[5]

References

edit
  1. ^ Papp, L., Merz, B. & Földvari (2006): Diptera of Thailand. A summary of the families and genera with references to the species representations. Acta. zool. hung. Vol. 52 (2)
  2. ^ R. W. Bouchard Jr. (2005). Guide to Aquatic Invertebrates of the Upper Midwest. University of Minnesota. Archived from the original on 2009-03-05. Retrieved 2007-06-30.
  3. ^ R. H. L. Disney (1999). British Dixidae (meniscus midges) and Thaumaleidae (trickle midges): keys with ecological notes. Vol. 56. Freshwater Biological Association. pp. 128 pp. ISBN 0-900386-60-6.
  4. ^ New Zealand inventory of biodiversity. Dennis P. Gordon. Christchurch, N.Z.: Canterbury University Press. 2009–2012. p. 328. ISBN 978-1-877257-72-8. OCLC 340800193.{{cite book}}: CS1 maint: others (link)
  5. ^ Greenwalt, D (2016). "The first fossil New World Dixidae with a critical discussion of generic definitions". Palaeontologia Electronica. doi:10.26879/656. ISSN 1094-8074.

Further reading

edit
  • Lindner, E 193 1. Dixinae (Culicidae) 3, 11–12, 1-43 In: Lindner, E. (Ed.). Die Fliegen der Paläarktischen Region Keys to Palaearctic species but now needs revision (in German).
  • A. A. Shtakel'berg Family Dixidae in Bei-Bienko, G. Ya, 1988 Keys to the insects of the European Part of the USSR Volume 5 (Diptera) Part 2 English edition.Keys to Palaearctic species but now needs revision .
edit