''Sepsis fulgens'' is a small ant-mimicking fly sometimes called the "lesser dung fly", though this can also refer to any member of the distantly related fly family

Sphaeroceridae Sphaeroceridae are a family (biology), family of true flies in the order (biology), order Fly, Diptera, often called small dung flies, lesser dung flies or lesser corpse flies due to their saprophagous habits. They belong to the typical fly subo ...

Distribution

It is common in much of

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

North Africa North Africa (sometimes Northern Africa) is a region encompassing the northern portion of the African continent. There is no singularly accepted scope for the region. However, it is sometimes defined as stretching from the Atlantic shores of t ...

Middle East The Middle East (term originally coined in English language) is a geopolitical region encompassing the Arabian Peninsula, the Levant, Turkey, Egypt, Iran, and Iraq. The term came into widespread usage by the United Kingdom and western Eur ...

and the

Russia Russia, or the Russian Federation, is a country spanning Eastern Europe and North Asia. It is the list of countries and dependencies by area, largest country in the world, and extends across Time in Russia, eleven time zones, sharing Borders ...

n Far East. It tends to be less common at the northernmost areas of its range. In Northern Europe, it can be found from May to early October. In Southern Europe, it can be found year-round.

Biology

This fly is often seen visiting flowers in order to obtain a

carbohydrate A carbohydrate () is a biomolecule composed of carbon (C), hydrogen (H), and oxygen (O) atoms. The typical hydrogen-to-oxygen atomic ratio is 2:1, analogous to that of water, and is represented by the empirical formula (where ''m'' and ''n'' ...

meal. But it is most often associated with a variety of animal dung, particularly that of cow and horse, on which the female will lay her

eggs An egg is an organic vessel in which an embryo begins to develop. Egg, EGG or eggs may also refer to: Biology * Egg cell, the female reproductive cell (gamete) in oogamous organisms Food * Eggs as food Places * Egg, Austria * Egg, Switzerland ...

, and the

larva A larva (; : larvae ) is a distinct juvenile form many animals undergo before metamorphosis into their next life stage. Animals with indirect development such as insects, some arachnids, amphibians, or cnidarians typically have a larval phase ...

will feed. Male ''S. fulgens'' are often more common on dung, as it here that they will wait for the females. In fact, males are so keen, that they will very often mount any visiting fly that bears a slight resemblance to another ''Sepsis'', including other males, but they will quickly dismount again when the error is apparent. When a suitable mate is found the male will stay firmly attached to the female, and copulation will normally take place later and at another location. So attached are the pair that it usually takes a 180-degree maneuver for the couple to part company. ''S. fulgens'' are also known for their swarming behaviour, and these swarms have been estimated to sometimes reach 30,000 to 50,000. In places where these swarms takes place, there is often a distinctive odour.

Parasites

There are a number of parasites that are associated with ''S. fulgens'', particularly the

mite Mites are small arachnids (eight-legged arthropods) of two large orders, the Acariformes and the Parasitiformes, which were historically grouped together in the subclass Acari. However, most recent genetic analyses do not recover the two as eac ...

s '' Bonomoia sphaerocerae'' and '' Macrocheles insignitus'', and possibly the

nematode The nematodes ( or ; ; ), roundworms or eelworms constitute the phylum Nematoda. Species in the phylum inhabit a broad range of environments. Most species are free-living, feeding on microorganisms, but many are parasitic. Parasitic worms (h ...

'' Diplogaster coprophila''.

References

{{Taxonbar, from=Q7452024 Diptera of Europe Diptera of Asia Taxa named by Johann Wilhelm Meigen Sepsidae Insects described in 1826