Two-winged Flies
The Diptera or two-winged flies, are traditionally one of the most neglected groups of British insects,
despite the fact that the 6,000 plus species form a very substantial proportion of the 21,000 or so insect
taxa recorded from the British Isles. It is only in the last 25 years that any systematic attempt has been
made to survey the Diptera fauna of Epping Forest and to date some 890 species are reported from
the Forest, although not all these records are published. Henry Doubleday provides us with the first
record - the rare cranefiy Ctenophora flaveolata. The specimen is in the Natural History Museum
collection.
Flies exploit an extremely wide range of habitats. In the Forest you will find them as larvae, in ponds
and ditches; mining the stems, leaves, roots and fruits of a wide variety of plants; in rot-holes in trees,
in decaying wood, underneath bark; in fungi; in bees and wasps and ant nests: in aphid galls; in fact
almost anywhere. Some species are typically associated with a particular type of habitat, i.e. ancient
woodland, grassland or heathland. Speight (1989). in a paper on the conservation of European Diptera,
included a list of some sixty species of old forest flies, the distributions of which were sufficiently
localised to suggest that their occurrence could be regarded as indicating that the Forest may be of
international scientific interest for nature conservation. Amongst the flies listed were four species -
Pocota personata, Ferdinandea ruficornis. Ctenophora flaveolata and Solva maculata, which have
all been reported from Epping Forest. The forest is rich in other less rare species of ancient woodland
flies, most of which are associated with rot-holes, decaying wood and sap-runs (saproxylic species)
on trees (see page 25). A checklist of flies recorded from the Forest is given below (Table 1).
Nomenclature follows Kloet and Hincks (1975) with additions and amendments to 1991.
At least five species of fly from three families have been recorded as new to science from the Forest.
Chironomidae
F. W. Edwards, an entomologist at the Natural History Museum, described two minute species of
non-biting midge from the Forest. He took two females of the fly he later named Corynoneura
fuscihalter in the Forest on 21st May. 1929. Edwards had previously taken a male Chironomid in
August. 1919 and then a female on 24th June. 1929 of a hitherto undescribed species from the Wake
Valley Pond. He named this species Paraphaenocladius cuneatus. The two new species were both
described in 1929. Types are held in the national collection (F. W. Edwards. Non-biting Midges
(Diptera: Chironomidae) Trans. Roy. Ent. Soc. Lond., 77, p. 279-430).
Phoridae
Dr. Ian McLean, of the Nature Conservancy Council, captured a small black fly of this family at
the Cuckoo Pits on 25th September, 1982. The fly was subsequently named by R. H. L. Disney as
Megaselia mcleani in honour of its finder (R. H. L. Disney (1987) Ent. Gaz., 38, p. 67-72).
Sphaeroceridae
O. W. Richards described two new species of lesser dung-fly from the Forest in 1929. both species
being found on cow dung on 18th September, 1927. The first of these Opalimosina collini (formerly
Leptocera collini) is known, apart from the Epping specimens, from only two other females taken in
Britain. The second species. Opalimosina simplex, was originally described by Richards as Leptocera
grenstedi var. simplex. Apart from the type specimens, the only other records of this species are from
Czechoslovakia (O. W. Richards (1930) The British Species of Sphaeroceridae (Borboridae, Diptera)
Proc. Zool. Soc. Lond.. 2. p. 261-345) and B. Pitkin (1988) Lesser Dung-flies (Diptera:
Sphaeroceridae) Handbk.Ident.Br.lns..Vol.X.pt.5e,p.44 (R.E.S.)).
References
Hanson. M. W (1983) Lords Bushes: The history and ecology of an Epping Forest woodland. Essex Naturalist (New Series) No. 7. p. 50-54.
Hanson. M.W. (1985) A Provisional List of the Larger Brachycera, Syrphidae and Conopidae of the Epping Forest area. Proc. Trans. Br. Ent.
Nat. Hist. Soc. 18. p. 37-48.
Hanson. M. W, (1991) Diptera in the Epping Forest area, Br. J. Ent. Nat. Hist. 4. p. 13-14.
Kloet. G S. and Hincks. W, D. (1975) A Checklist of British Insects. Diptera and Siphonaptera. Handbk.Ident.Br.Ins.XK5)
Payne, R. M. (1968) The Crane Flies (Diptera: Tipulidae) of Epping Forest. Ent. Gaz 19. p. 35-43.
Snow. K R. and Fallis. S. P. (1982) The Mosquitoes of Epping Forest, London Naturalist No.61, p.65-71
Speight. M C D (1989) The Council of Europe and the Conservation of Diptera Dipterists Digest No. 2, p.3-7.
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