Vol 10 Part 14. An introduction to the immature stages of British Flies ...

masses of Dixa (Dixidae) and larvae of Phaonia exoleta (Meigen) (Muscidae) feed on
mosquito (Culicidae) larvae.
Some may also be attacked by adult Diptera, e.g. chironomid larvae are attacked by
adult Dolichopodidae (Hydrophorus, Campsicnemus, Poecilobothrus and Dolichopus)
(Smith & Empson, 1955). Simuliid larvae have been reported to be attacked by adult
Empididae (Ciinocerinae and Hemerodromiinae) and Dolichopodidae in Canada
(Davies, D . M., 1981).
On plants, predaceous larvae of Lestodiplosis are commonly found feeding on larvae
of other Cecidomyiidae (Harris, 1966).
In the U.S.A. water mites have been recorded as predators on the eggs and larvae of
mosquitoes (Mullen, 1975).
Parasites
Parasites of Diptera should always be carefully preserved with all the relevant
puparial fragments, etc. and data, as much remains to be discovered and many rea rings
in the literature are in need of careful confirmation.
The Hymenoptera provide the most important parasites of immature Diptera. A
general survey is given by Shaw & Askew (in Stubbs & Chandler, 1978) and Smith
(1974b). The principal parasites are as follows: Ichneumonidae (Phygadeuon (fig.
1321), Mesoleptus and related genera on fly puparia, Oxytorinae on Mycetophilidae,
Orthocentrinae on Diptera near the ground, Diplazontinae on aphidophagous
Syrphidae): Braconidae (Opiinae on plant feeding Schizophora, Alysiinae (figs 1319,
1320) on Cyclorrhapha); Eulophidae; Pteromalidae; some Ceraphrontoidea; Proctotrupoidea
(Piatygastridae on Cecidomyiidae); Diapriidae (Diapriinae on cyclorrhaphous
puparia, Belytinae on Mycetophilidae), Scelionidae, Trichogrammatidae,
Mymaridae (all of the last three families are egg parasites on some Cecidomyiidae,
Tabanidae, Rhagionidae and Syrphidae); Cynipoidea (Eucoilidae and Figitidae on
Cyclorrhapha).
In the Coleoptera some larvae of Staphylinidae, e.g. Aleochara, are parasites of fly
puparia, mostly calypterates and especially Anthomyiidae (see Welch, 1965). The
species of fly parasitised probably varies with the habitat, e.g. Aleochara algarum
Fauvel is parasitic on seaweed flies such as Coelopa and Orygma, while A. cur tu/a
(Goeze) is a common parasite in the puparia of blowflies (figs 1322- 1326).
Parasitism of Diptera by Diptera is not common and the few British records (see
under family for details) may be summarised as follows:
Tachinidae: Siphona on leatherjacket larvae of Tipulidae and a Pegomya sp.;
Admontia (Trichopareia) specialises in Tipulidae in wood, e.g. Ctenophora, Tipula
irrorata Macquart and T.jlavolineata Meigen.
Phoridae: Borophaga incrassata Meigen parasitizes larvae of Bibio marci L.; M egaselia
paludosa Wood attacks leatherjackets; M .jlavicoxa Zetterstedt parasitises larvae of
Bradysia bicolor Meigen (Sciaridae); and M. obscuripennis Wood is a parasite of larvae
of Trichosia (Sciaridae).
In the U .S.A. Macronychia (Sarcophagidae) has been reared from adult Tabanidae
and some Tachinidae have been reared from larval and adult Tabanidae (Thompson,
P. H ., 1978). In Australia a tachinid has been reared from an adult Atherigona (Muscidae)
(Smith, 1974c, Ferrar, 1977).
Parasitic fungi probably also take a steady toll oflarvae, as they do of adults, though
few are recorded specifically from Diptera larvae in the literature (Leatherdale, 1970).
I have found the larvae of Lonchaea palposa Zetterstedt infested with the 'green
muscardine' fungus Metarrhizium anisopliae (Metsch) (Smith, 1957b). D'Arcy-Burt
( 1987) reports the hyphomycete Tolypocaladium cylindrosporum Gams from the larvae
of Bibionidae. Abroad, but not yet in Britain, species of Coelomomyces fungi have been
found in the larvae of mosquitoes.
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