Sepsidae

Sepsidae
Sepsis fulgens (lesser dung fly)
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Diptera
Suborder:	Brachycera
Subsection:	Acalyptratae
Superfamily:	Sciomyzoidea
Family:	Sepsidae
Genera
see text

Sepsis sp. on grass (video, 59s)

Sepsidae are a family of flies, commonly called the black scavenger flies or ensign flies. There are approximately 250 species worldwide. They are usually found around dung or decaying plant and animal material. Many species resemble ants having a "waist" and glossy black body. Many Sepsidae have a curious wing-waving habit made more apparent by dark patches at the wing end.

Many species have a very wide distribution, reflecting the coprophagous habit of most Sepsidae. Some species have been spread over large territories in association with livestock. Adult flies are found mostly on animal and human excrement (less often on other rotting organic matter), where eggs are laid and larvae develop, and on nearby vegetation, carrion, fermenting tree sap, and shrubs and herbs.

Many Sepsidae apparently play an important biological role as decomposers of animal excrement. Some species may have a limited hygienic importance because of their association with human feces. Others are useful tools in forensic entomology.

Description

Sepsidae morphology

For terms see Morphology of Diptera. Slender flies with relatively few bristles or hairs resembling minute winged ants. The colour is usually black, sometimes lustrous black and with silvery pruinosity on the side of the thorax. (Orygma luctuosum Meigen, a robust, hairy, flattened fly associated with seaweed) The head is rounded. The postvertical bristles are divergent (in some species postvertical bristles absent).There are 0-3 pairs of frontal bristles. Ocelli and ocellar bristles are present. Vibrissae are poorly developed and the palpi are underdeveloped.The presence of 1 or more bristles at the posteroventral margin of the posterior spiracle of the thorax distinguishes Sepsidae from all other Acalyptrata. In the male the femur and tibia of the fore legs often has extrusions, spurs, teeth and other ornament. Tibiae usually with dorsal preapical bristle (small or absent in Meroplius, Nemopoda, Themira). The costa is without interruptions and either wings with dark round spot near apex of R1 (Sepsis) or clear or tinged. The subcostal vein is complete, crossvein BM-Cu is present and the anal cell (cell cup) is closed. The abdomen is usually constricted in the basal part.

The larva is amphipneustic (having only the anterior and posterior pairs of spiracle) slender tapering at the anterior,and smooth except for ventral creeping welts. It is distinguished from other acalyptrate larvae by a somewhat bulbous spiculate posterior end. The anterior spiracles (prothoracic spiracles) are dendritic, usually with an elongated median axis. The posterior spiracles (on the anal segment) are pleced on basally joined spiracular plates at the end of a short constriction at the posterior end of body.The constriction usually bears accessory processes.

The pupae is enclosed within a puparium.

Classification

List of Genera^[1]

See also

• List of sepsid fly species recorded in Europe

References

Further reading

Identification

• Duda, O. 1926 Monographie der Sepsiden (Dipt.). Ann. Naturhist. Mus. Wien 39 (1925): 1-153 and 40 (1926) : 1-110.This work is partly out of date but still the only review of world genera.
• Willi Hennig, 1949: 39a. Sepsidae. In Erwin Lindner : Die Fliegen der Palaearktischen Region, Bd. V: 1-91, Textfig. 1-81a-d, Taf. I-X, Stuttgart.The only comprehensive work on Palaearctic genera and species.
• Adrian C. Pont and Rudolf Meier The Sepsidae (Diptera) of Europe. Fauna Entomologica Scandinavica Volume 37. 198 pages. ISBN 90-04-12477-2
• A.L. Ozerov Sepsid Flies (Diptera, Sepsidae) of Russia's Fauna. Studies on the fauna; Archives of the Zoological Museum of Moscow State University: Zool. Mus. Moscow. Univ. Publ.Language: Russian, title, contents and a summary in English. 184 pages.A very well illustrated guide to all 57 species from 11 genera of Sepsidae flies occurring in Russia, with keys to adults and pre-imaginal stages, and accounts concerning anatomy, phylogeny and distribution.
• Silva, V. C. . Revisao da familia Sepsidae na regiao Neotropical. Iii. Os generos Palaeosepsis Duda, 1926, Archisepsis Gen. N. e Microsepsis Gen. N., Chave para os Generos Neotropicais (Diptera, Schizophora). Iheringia. Série Zoologia, v. 75, p. 117-170, 1993.
• Silva, V. C. . Revision of the family Sepsidae of the Neotropical region. ii. The genus Meropliosepsis Duda, 1926 (Diptera, Schizophora). Revista Brasileira de Entomologia, v. 36, n. 3, p. 549-552, 1992.
• K. G. V. Smith, 1989 An introduction to the immature stages of British Flies. Diptera Larvae, with notes on eggs, puparia and pupae.Handbooks for the Identification of British Insects Vol 10 Part 14. pdf download manual (two parts Main text and figures index)

World catalogue

• Ozerov, A.L. World catalogue of the family Sepsidae (Insecta: Diptera), Zoologicheskie issledovania (Zoological Studies), No. 8 (ISSN 1025-532X)

Species lists

• West Palaearctic including Russia
• Nearctic
• Australasian/Oceanian
• Japan

External links

Wikimedia Commons has media related to Sepsidae.

• Family Sepsidae at EOL
• Black Scavenger Fly - diagnostic photographs
• Family description and images
• Images of Sepsidae on Diptera.info