![Microdon Eggeri larvae third instar (by Maria andries, 1912)](https://upload.wikimedia.org/wikipedia/commons/5/5b/Microdon_Eggeri_larvae_third_instar_%28by_Maria_andries%2C_1912%29.jpg)
Hover flies (family
Syrphidae) of the genus ''Microdon'' are unusual among the
Diptera
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 ...
. Like other members of the subfamily, they are
myrmecophile
Myrmecophily ( , ) is the term applied to positive interspecies associations between ants and a variety of other organisms, such as plants, other arthropods, and fungi. Myrmecophily refers to mutualistic associations with ants, though in its m ...
s, meaning they inhabit the nests of ants.
There are 249 species known worldwide, with the greatest diversity being from the
tropics
The tropics are the regions of Earth surrounding the Equator. They are defined in latitude by the Tropic of Cancer in the Northern Hemisphere at N and the Tropic of Capricorn in
the Southern Hemisphere at S. The tropics are also referred to ...
; 30 species are known from North America, though it is expected that many of these species will be placed in other genera in time, as ''Microdon'' has been used as a catch-all for various unrelated species not placed in other genera.
Appearance
''Microdon'' adults look more or less like typical flies. Like some other hoverflies, they are generally robust and very hairy, often closely resembling bees. They are between 8 and 15 mm long. The
antenna
Antenna ( antennas or antennae) may refer to:
Science and engineering
* Antenna (radio), also known as an aerial, a transducer designed to transmit or receive electromagnetic (e.g., TV or radio) waves
* Antennae Galaxies, the name of two collid ...
e are rather long, with the last (third) segment nearly as long as, or sometimes significantly longer than, the first segment; the antennae are nearly as long as the fly's face. These flies are covered in black or pale (white or golden) hairs, and are themselves either black or metallic green or blue. The
scutellum is with apical
calcar
The calcar, also known as the calcaneum, is the name given to a spur of cartilage arising from inner side of ankle and running along part of outer interfemoral membrane in bats, as well as to a similar spur on the legs of some arthropods.
The cal ...
s and wing vein R4+5 with an appendix. They have simple legs and abdomens.
The real oddity of the genus ''Microdon'' is in its larvae and pupae. These are dome-shaped and look like stout little slugs. Their appearance originally led scientists to describe them as
mollusk
Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is e ...
s and
scale insect
Scale insects are small insects of the order Hemiptera, suborder Sternorrhyncha. Of dramatically variable appearance and extreme sexual dimorphism, they comprise the infraorder Coccomorpha which is considered a more convenient grouping than the ...
s.
They are slow-moving. Most have the
spiracles on a peg-like protuberance extending from the end of their abdomens.
Behaviour
Adult ''Microdon'' flies do not behave like other syrphid flies; they do not hover around flowers, but instead remain very near the ant colonies which serve as larval hosts.
Larvae may be found very deep in ant colonies. Some species actively feed on ant larvae in the colony,
others are speculated to be scavengers. ''Microdon'' larvae are more or less restricted in their ant host species. Some ''Microdon'' species have only ever been found in the colonies of a single ant species, while others are restricted to related ant species or genera. Because these flies have such cryptic life cycles, biological information on most species is limited.
Species
''Microdon'' is divided into six subgenera (including ''Microdon'' s.s.), plus five species groups and some unplaced species in "''Microdon'' s.l.".
Subgenus ''Chymophila''
Nearctic:
* '' Microdon fulgens'' Wiedemann, 1830 (Synonyms: ''Microdon euglossoides'' Gray, 1832; ''Chymophila splendens'' Macquart, 1834)
Neotropical:
Oriental:
Palaearctic:
* '' Microdon katsurai'' Maruyama & Hironaga, 2004
Subgenus ''Dimeraspis''
*'' Microdon abditus'' Thompson, 1981 [
*'' Microdon adventitius'' Thompson, 1981 ][ ]
*'' Microdon fuscipennis'' (Macquart, 1834)
*'' Microdon globosus'' (Fabricius, 1805)[ ?]
*'' Microdon marmoratum'' Bigot, 1884
*'' Microdon remotus'' Knab, 1917[ ]
Subgenus ''Megodon''
*'' M. planitarsus'' Keiser, 1971
*'' M. stuckenbergi'' (Keiser, 1971)
Subgenus ''Microdon'' s.s.
Nearctic
The Nearctic realm is one of the eight biogeographic realms constituting the Earth's land surface.
The Nearctic realm covers most of North America, including Greenland, Central Florida, and the highlands of Mexico. The parts of North America t ...
:
Neotropical
The Neotropical realm is one of the eight biogeographic realms constituting Earth's land surface. Physically, it includes the tropical terrestrial ecoregions of the Americas and the entire South American temperate zone.
Definition
In bioge ...
:
Oriental:
Palaearctic
The Palearctic or Palaearctic is the largest of the eight biogeographic realms of the Earth. It stretches across all of Eurasia north of the foothills of the Himalayas, and North Africa.
The realm consists of several bioregions: the Euro-Sibe ...
:
Subgenus ''Myiacerapis''
''Myiacerapis'' is a subgenus
In biology, a subgenus (plural: subgenera) is a taxonomic rank directly below genus.
In the International Code of Zoological Nomenclature, a subgeneric name can be used independently or included in a species name, in parentheses, placed between t ...
of the 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 ...
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
''Microdon''. It contains only one species, ''Microdon villosus.''It is native to Uganda
}), is a landlocked country in East Africa
East Africa, Eastern Africa, or East of Africa, is the eastern subregion of the African continent. In the United Nations Statistics Division scheme of geographic regions, 10-11-(16*) territor ...
, though an undescribed species is known from South Africa
South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring countri ...
.[ ]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.
The ...
e are found in ant
Ants are eusocial insects of the family Formicidae and, along with the related wasps and bees, belong to the order Hymenoptera. Ants evolved from vespoid wasp ancestors in the Cretaceous period. More than 13,800 of an estimated total of 22 ...
nests.
Subgenus ''Syrphipogon''
There are two species described in ''Syrphipogon'':[
*'' M. fucatissimus'' ( Hull, 1937)
*'' M. gaigei'' Steyskal, 1953
]
''Microdon'' s.l. species groups
''craigheadii''-group
Nearctic:
* '' Microdon craigheadii'' Walton, 1912
''erythros''-group
Afrotropical
The Afrotropical realm is one of Earth's eight biogeographic realms. It includes Africa south of the Sahara Desert, the majority of the Arabian Peninsula, the island of Madagascar, southern Iran and extreme southwestern Pakistan, and the island ...
:
* '' Microdon erythros'' Bezzi, 1908
:= ''Microdon erytherus'' Bezzi, 1921 (misspelling)
* '' Microdon luteiventris'' Bezzi, 1915
''mirabilis''-group
Neotropical
The Neotropical realm is one of the eight biogeographic realms constituting Earth's land surface. Physically, it includes the tropical terrestrial ecoregions of the Americas and the entire South American temperate zone.
Definition
In bioge ...
:
* '' Microdon bertonii'' Bezzi, 1910
:= ''Microdon arcuata'' Curran, 1941
* '' Microdon iheringi'' Bezzi, 1910
* '' Microdon mirabilis'' Williston, 1888
''tarsalis''-group
Afrotropical:
* '' Microdon tarsalis'' Hervé-Bazin, 1913
:= ''Microdon bequaerti'' Curran, 1929
Unplaced species
Afrotropical
The Afrotropical realm is one of Earth's eight biogeographic realms. It includes Africa south of the Sahara Desert, the majority of the Arabian Peninsula, the island of Madagascar, southern Iran and extreme southwestern Pakistan, and the island ...
*'' Microdon harinhalai'' (Reemer, 2015) [ ]
*'' Microdon berobak'' (Reemer, 2015) [
*'' Microdon ifanadiana'' (Reemer, 2015) ][
*'' Microdon irwini'' (Reemer, 2015) ][
*'' *Microdon_janne''_(Reemer,_2015)_
*''Microdon_sava.html" ;"title="Microdon_janne.html" ;"title="*Microdon janne">*Microdon janne'' (Reemer, 2015) ][
*''Microdon sava">Microdon_janne.html" ;"title="*Microdon janne">*Microdon janne'' (Reemer, 2015) ][
*''Microdon sava'' (Reemer, 2015) ][
* ''Microdon tsara'' Keiser, 1971
Australasian realm, Australian / Oceanian realm, Oceanian:
* ''Microdon amabilis'' Eustace William Ferguson, Ferguson, 1926
* '' Microdon macquariensis'' Eustace William Ferguson, Ferguson, 1926
* '' Microdon nigromarginalis'' Curran & Bryan, 1926
* '' Microdon pictipennis'' ( Macquart, 1850)
:= ''Microdon pictulipennis'' Hull, 1944
* '' Microdon rieki'' Paramonov, 1957
* '' Microdon waterhousei'' Eustace William Ferguson, Ferguson, 1926
Oriental:
* '' Microdon carbonarius'' Brunetti, 1923
* '' Microdon pagdeni'' Curran, 1942
* '' Microdon trimacula'' Curran, 1928
* '' Microdon unicolor'' Brunetti, 1915
]
References
{{Taxonbar, from=Q115951
Hoverfly genera
Microdontinae
Myrmecology
Taxa named by Johann Wilhelm Meigen