Scathophagidae

Not to be confused with Scatophagidae, a fish family.

Scathophagidae
Male Scathophaga stercoraria (L.), the Common Yellow Dung-fly.
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Diptera
Section:	Schizophora
Superfamily:	Muscoidea
Family:	Scathophagidae
Subfamilies
Scathophaginae Delininae
Synonyms
Cordyluridae Scatophagidae Scopeumatidae Scatomyzidae

The Scathophagidae is a small family of Muscoidea which are often known as "Dung-flies" although this name is not appropriate except for a few species of the genus Scathophaga which do indeed pass their larval stages in animal dung. The name probably derives from the "Common Yellow Dung-fly", S. stercoraria, which is one of the most abundant and ubiquitous flies in many parts of the northern hemisphere.

Description

For terms see Morphology of Diptera.

Scathophagidae are medium-sized or quite small flies with a body length of 3.0 to 12.0 mm. The body is slender, especially in males, usually with an elongate cylindrical abdomen. Many Scatophaga appear more robust, however, due to a dense pubescence. Colour of body from yellow to black; some species are glossy, but never with a metallic gloss. Some species are bicolourous. The eyes are wide-set on the frons in males as well as females. The bristles on the head, thorax and legs are well developed. Occiput usually with pale, long hairs. The arista is bare to plumose. Interfrontal bristles are absent. The wing is usually clear but in some species has distinct marks or darkening at the tip or along the crossveins. The anal vein is long and usually reaches the wing margin. The meron is without bristles along the hind margin, near the posterior spiracle.

Hunting Cordilura on leaves of blackberry (video, 57s)

Biology

The larval-biology of this family is actually quite diverse including plant feeders (leaf miners, stem-borers or feeding in seed capsules), aquatic predators and predators on other insect larvae in wet situations - such as piles of rotting vegetable matter, seaweed or dung. The adults are predators on other small insects, and while they are commonly seen on flowers, they are hunting prey there, rather than acting as pollinators. They are, in fact, one of the better predators of blow-flies, and are thus beneficial agents of biological control. Some species are attracted to dung in great numbers. One of the best-known species of this family is Scathophaga stercoraria (Linnaeus). The reddish-brown densely pilose males of this gather on cow dung and may, in parts of its range be observed at all times of the year.

Worldwide, there are about 500 described species in 66 genera. The great majority are found in the Palearctic and Nearctic regions and the family is almost confined to the northern hemisphere with only 5 species so far known from the southern hemisphere (and two of those are common northern species of Scathophaga which have probably been imported with livestock into South Africa and Brazil). The most diverse fauna is found in the Russian Far East and many new species have been described from this area over the last couple of decades. Because of the northerly distribution of many species, even within the Holarctic, Vockeroth (1987) has described this as the most northerly-distributed of all fly families. He reports that, of the 150 species recorded from Canada, 25 are confined to the arctic tundra.

54 species are currently recorded from the British Isles and nearly all of these have a Holarctic distribution.

Literature

Identification

• K.B. Gorodkov Family Scatophagidae (Cordyluridae, Scatomyzidae, Scopeumatidae) 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 .
• Hackman, W., 1956. The Scatophagidae (Dipt.) of Eastern Fennoscandia. Societas Fauna Flora Fennica, Fauna Fennica 2: 1-67, Fig. 1-165, Helsinki.
• Sack, 1937. Coryluridae. In: Lindner, E. (Ed.). Die Fliegen der palaearktischen Region , 7, 62a, 1-103.
• Séguy, E., 1934 Diptères: Brachycères. II. Muscidae acalypterae, Scatophagidae. Paris: Éditions Faune de France 28. virtuelle numérique

External links

• Image Gallery from Diptera.info
• Image Gallery from BuG Guide
• Family Scathophagidae at EOL Image Gallery

Species lists

• Palaearctic
• Nearctic
• Japan
• Australasian/Oceanian
• World list