''Myolepta potens'' is a

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a subcontinent of Eurasia and it is located enti ...

hoverfly Hover flies, also called flower flies or syrphid flies, make up the insect family Syrphidae. As their common name suggests, they are often seen hovering or nectaring at flowers; the adults of many species feed mainly on nectar and pollen, while ...

. The species ranges from

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of overseas regions and territories in the Americas and the Atlantic, Pacific and Indian Oceans. Its metropolitan ar ...

and

Germany Germany, officially the Federal Republic of Germany (FRG),, is a country in Central Europe. It is the most populous member state of the European Union. Germany lies between the Baltic and North Sea to the north and the Alps to the sou ...

through

central Europe Central Europe is an area of Europe between Western Europe and Eastern Europe, based on a common historical, social and cultural identity. The Thirty Years' War (1618–1648) between Catholicism and Protestantism significantly shaped the ...

to the

Black Sea The Black Sea is a marginal mediterranean sea of the Atlantic Ocean lying between Europe and Asia, east of the Balkans, south of the East European Plain, west of the Caucasus, and north of Anatolia. It is bounded by Bulgaria, Georgia, ...

. It is rare throughout its range and is listed in the

Red Data Book The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biolog ...

s of a number of its

range state Range state is a term generally used in zoogeography and conservation biology to refer to any nation that exercises jurisdiction over any part of a range which a particular species, taxon or biotope inhabits, or crosses or overflies at any time on ...

s. It is listed by the Council of Europe as a

Saproxylic Xylophagy is a term used in ecology to describe the habits of an herbivorous animal whose diet consists primarily (often solely) of wood. The word derives from Greek ''ξυλοφάγος'' (''xulophagos'') "eating wood", from ''ξύλον'' (') ...

(deadwood-dependent)

Indicator species A bioindicator is any species (an indicator species) or group of species whose function, population, or status can reveal the qualitative status of the environment. The most common indicator species are animals. For example, copepods and other sma ...

, because its presence indicates that a large quantity of standing deadwood is also present. The species was discovered in

Britain Britain most often refers to: * The United Kingdom, a sovereign state in Europe comprising the island of Great Britain, the north-eastern part of the island of Ireland and many smaller islands * Great Britain, the largest island in the United King ...

in 1945 by John Cowley at Loxley Wood and another

woodland A woodland () is, in the broad sense, land covered with trees, or in a narrow sense, synonymous with wood (or in the U.S., the '' plurale tantum'' woods), a low-density forest forming open habitats with plenty of sunlight and limited shade (see ...

site near Shapwick in

Somerset ( en, All The People of Somerset) , locator_map = , coordinates = , region = South West England , established_date = Ancient , established_by = , preceded_by = , origin = , lord_lieutenant_office =Lord Lieutenant of Somerset , lor ...

and identified by J. E. Collin. Cowley found more specimens in the same area in 1946, 1947 and 1949. Subsequently, fellow

dipterist Flies are insects of the order Diptera, the name being derived from the Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwings having evolved into advanced m ...

E. C. M. d'Assis-Fonseca found a single male in Blaise Wood near

Bristol Bristol () is a city, ceremonial county and unitary authority in England. Situated on the River Avon, it is bordered by the ceremonial counties of Gloucestershire to the north and Somerset to the south. Bristol is the most populous city i ...

in 1949, and in 1950 E. E. Lowe found the species at Combe Dingle, which is close to the

Blaise Castle Estate Blaise Castle is a folly built in 1766 near Henbury in Bristol, England. The castle sits within the Blaise Castle Estate, which also includes Blaise Castle House, a Grade II* listed 18th-century mansion house. The folly castle is also Grade ...

within which Blaise Wood lies. J. C. Hartley found six

larva A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. Th ...

e in a rot-hole at

Ashton Court Ashton Court is a mansion house and estate to the west of Bristol in England. Although the estate lies mainly in North Somerset, it is owned by the City of Bristol. The mansion and stables are a Grade I listed building. Other structures on th ...

, Bristol in 1961, thus providing proof of the species' breeding in Britain. Despite attempts to relocate the species in its Bristol and Somerset sites in the 1980s and 1990s, it has not been refound (Loxley Wood is largely coniferised and therefore no longer suitable for supporting the species). In the

Institute for Terrestrial Ecology An institute is an organisational body created for a certain purpose. They are often research organisations ( research institutes) created to do research on specific topics, or can also be a professional body. In some countries, institutes c ...

's Provisional hoverfly atlas published in 2000, the species was listed as extinct. During an

English Nature English Nature was the United Kingdom government agency that promoted the conservation of wildlife, geology and wild places throughout England between 1990 and 2006. It was a non-departmental public body funded by the Department for Environme ...

-commissioned survey of

Moccas Park National Nature Reserve Moccas is a village and civil parish in the English county of Herefordshire. It is located west of Hereford. The population of the civil parish taken at the 2011 census was 105. The parish is mainly farmland with a number of woods, includin ...

Herefordshire Herefordshire () is a county in the West Midlands of England, governed by Herefordshire Council. It is bordered by Shropshire to the north, Worcestershire to the east, Gloucestershire to the south-east, and the Welsh counties of Monmouthshire ...

, Andy Godfrey found ''Myolepta potens'' larvae in a rot-hole. Subsequent survey work revealed that there is a strong population at this site using rot holes in several different species of tree. Two English names have been coined for this species, although neither has gained widespread usage: the Western wood-vase hoverfly and the Moccas hoverfly

References

{{DEFAULTSORT:Myolepta Potens Eristalinae Diptera of Europe Insects described in 1776 Taxa named by Moses Harris