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

Status Until recently a poorly known species. Although still
appearing to be rare, it is proving to be widespread in
England and the Irish record suggests that it could
potentially occur further north also. Not listed in Shirt
(1987). Status revised from RDB 2 (Falk 1991). This is the
Mycetophila sp. nov. of Falk (1991).
Threats Clearance of damp woodland for intensive forestry
or agriculture. Removal of dead wood and old or diseased
trees, which might support suitable fungi. Drainage of
marshy areas and ditching of streams.
Management and conservation Maintain woodlands in a
natural state, retaining any old or diseased trees and dead
wood, especially in damp shaded situations favoured by
fungi. Avoid drainage of marshy areas and ensure that
woodland streams remain shaded and undisturbed.
Published sources Chandler (1988); Miles (1991); Perry &
Langton (2000).
MYCETOPHILA V-NIGRUM
A fungus gnat
DATA DEFICIENT
Order DIPTERA
Family MYCETOPHILIDAE
Mycetophila v-nigrum Lundström, 1913
Identification The male genitalia were figured by
Lundström (1913).
Distribution Only known as British on seven records of
males: Canford Heath, Dorset (1993); Ashberry Pastures
(1990) and Scargill (1992), Yorkshire; Randolph’s Leap,
Elgin (2004); Belladrum Burn (1984) and Drumnadrochit
(1989), Easterness; Bonhill, Dunbartonshire (1907).
Females from Kent and Argyllshire are provisionally
considered conspecific but this has not yet been confirmed.
Habitat Damp broad-leaved woodland with streams.
Ecology Biology unknown. The larvae probably develop in
lignicolous fungi. Adults recorded in April, June and
September to October.
Status Poorly known but six of the seven confirmed records
are post 1980; possibly overlooked elsewhere in this wide
range due to low population levels. Currently there is
inadequate information to assess the risk of extinction. Not
listed in Shirt (1987). Status revised from RDB 2 (Falk
1991).
Threats Clearance of woodland for intensive forestry or
agriculture. Removal of any dead wood and old or diseased
trees, which might support fungus hosts.
Management and conservation Maintain woodlands in a
natural state, retaining any old or diseased trees and dead
wood, especially in damp shaded situations. Avoid drainage
of marshy areas or disturbance of woodland streams, which
should remain shaded.
Published sources Chandler (1988).
MYCOMYA BRANDERI
A fungus gnat
Order DIPTERA
Mycomya branderi Väisänen, 1984
VULNERABLE
Family MYCETOPHILIDAE
Identification The male genitalia were figured by Väisänen
(1984) and by Chandler (1992b), who also figured the entire
insect. This species is very close to the North American
Mycomya tantilla Loew, but was separated by Väisänen on
proportional differences in the male genitalia.
Distribution Only known from two sites in Norfolk: Old
Buckenham Fen and Strumpshaw (both June to July 1988,
A. Foster and D. Procter).
Habitat Fenland. The Old Buckenham Fen site, where it
was found in large numbers, consists chiefly of Phragmites
beds adjoining a small broad-leaved wood.
Ecology Biology unknown. The larvae of this genus have
been reared from fungi or associated with fungi on damp
rotten wood and are web spinners living on the surface of
this substrate.
Status A recent addition to the British list, but a distinctive
species which has not been found again since 1988.
Evidently restricted in range because it was not found at
other sites during the survey of East Anglian wetlands, but a
large population was present at Old Buckenham Fen.
Subsequent visits to the latter site have, however, failed to
confirm its continued existence there. Not listed in Shirt
(1987) or Falk (1991). It is otherwise known from Denmark
and Finland and hence the British population may be of
international significance.
Threats Unclear other than loss of habitat to agriculture or
forestry, overgrazing or non-rotational cutting of fens.
Removal of litter layer or decaying vegetation on which
fungal hosts may depend.
Management and conservation Maintain stable water
level and vegetation structure in fens; restrict any grazing
and ensure that any cutting is carried out on a long rotation.
Published sources Chandler (1992b).
MYCOMYA BRITTENI
A fungus gnat LOWER RISK (Nationally Scarce)
Order DIPTERA
Family MYCETOPHILIDAE
Mycomya britteni Kidd, 1955
Identification Keyed by Hutson, Ackland & Kidd (1980),
who figured the male genitalia; Chandler (1992b) figured
the ovipositor.
Distribution This was known only from the type locality at
Skirwith, Cumberland (24 August 1953) until it was found
by the NCC wetland surveys to be widespread in Wales
(thirteen sites in Monmouthshire, Pembrokeshire,
Cardiganshire, Denbighshire and Anglesey) and southern
England: Oxfordshire (Spartum Fen and Wychwood NNR),
Norfolk (seven sites) and Shropshire (Wem Moss).
Habitat Most sites are fens or mires.
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