Part 2: Nematocera and Aschiza not dealt with by Falk (1991) - JNCC

NNR), which are now in Oxfordshire, correctly belong to the Vice-county of Berkshire and are so
assigned here; also Goyt Valley, Derbyshire is in the Vice-county of Cheshire and is so assigned here in
view of its inclusion in their work on the Diptera of Lancashire and Cheshire by Kidd & Brindle (1959).
Boundary changes in the north of England have been most confusing but records have been assigned as
far as practicable on the basis of the divisions used by Falk (1991), e.g. Yorkshire is treated as a single
unit corresponding to the pre-1974 county.
In Wales all records are placed under the pre-1974 county names, which correspond almost entirely to
the Vice-counties. In Scotland most records had been assigned to Vice-county in the first draft by Steven
Falk except in the cases of Aberdeenshire, Perthshire or Sutherland, as stated in his Introduction (1991).
It has not been practicable to improve on the treatment of Perthshire in the present work; most
Aberdeenshire records relate to Vice-county 92 and Sutherland records are assigned to Vice-county. It is
unfortunate that the boundary of Vice-county 95 (Elgin) was drawn to take in part of the Spey Valley (as
far south as Aviemore), included in the former administrative county of Inverness-shire, while the county
of Nairn is included in Easterness, thus splitting the Culbin Forest area between these Vice-counties.
Counties and Vice-counties are listed in the ascending order of Watsonian numbering, except that
records for all English counties are listed first, and records for Wales are then listed separately. Where
records are limited, as in the more threatened species, then fuller details are provided. Where there are
five or fewer British records of a species, the names of the recorders are given.
3.4. Habitat
Few habitat descriptions are available, and the majority of records merely refer to a place-name. In some
instances the known collecting preferences of dipterists can be of some help, but caution must always be
exercised. Falk & Crossley (2005) give as an example Aviemore, suggesting that this might refer to
either the banks of the Spey or to some other location in the vicinity. In this context it should be noted
that the earlier generations of dipterists were not very precise about recording and sometimes labelled all
their captures for a particular trip with the name of the centre where they were staying and some species
labelled Aviemore might have been found at some miles from the town (although perhaps not necessarily
on the summit of Cairn Gorm). A case in point is the large number of fungus gnats (110 species)
recorded from Dingwall, East Ross, by J.J.F.X. King. He spent July and August 1909 at this centre; no
suitable habitat for this group of insects exists within the environs of the town and there is no reason to
suppose that it was any more favourable for them at that time.
Inevitably, many statements in this section are vague, and in some cases no attempt has been made to
compile a description due to lack of information. It is hoped that by drawing attention to these
obvious gaps in our knowledge in this way, dipterists will be encouraged to quote habitat details
when presenting future records. Fortunately, in the case of some species there is sufficient information
to enable reasonable inferences to be made.
3.5. Ecology
The life histories of many species in the families dealt with here are known, although a greater
proportion of the commoner species (not covered by this review) have their biology known; therefore,
gaps in our knowledge of the scarcer species are still considerable. The best known of the groups
included here are those with aquatic larvae (Ptychopteridae, Dixidae, Culicidae, Thaumaleidae and the
single species of Ceratopogonidae included). The larval habitats are also known for the Trichoceridae
and Mycetobiidae covered, and there is now information available on one of the three species of
Lonchopteridae listed. The Pipunculidae are well known to be internal parasitoids of Homoptera; this is
assumed to be the life style of all members of the family although there are confirmed associations for
relatively few of the species included here.
The Platypezidae and Mycetophilidae sensu lato are principally fungus feeders although some members
of most families in the latter group develop in other terrestrial habitats such as rotten wood, bryophytes,
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