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

Aberdeenshire (2000); Loch an Eilein (1982) and Abernethy
Forest NNR (1999), Easterness; Migdale Wood, East
Sutherland (1994).
Habitat Old broad-leaved woodland in England and Wales;
the Scottish sites include Betula and mixed Betula and
Pinus woodland.
Ecology Biology unknown; the larvae probably develop in
soft terrestrial fungi. Adults recorded from May to July and
in September.
Status First recorded in Britain in 1974 and only a further
sixteen sites have been added since. Thus still poorly known
but possibly under-recorded, as reflected by the wide
distribution. Status revised from RDB 2 (Shirt 1987).
Threats Clearance of old woodland for agriculture or
intensive forestry.
Management and conservation Maintain woodland in a
natural state with all successional stages to ensure its
continuity. Avoid damage to leaf litter or soil structure
which could affect the survival of the fungus hosts.
Published sources Chandler (1975).
CLASTOBASIS ALTERNANS
A fungus gnat LOWER RISK (Near Threatened)
Order DIPTERA
Family MYCETOPHILIDAE
Clastobasis alternans (Winnertz, 1863)
Identification The male genitalia were figured by Landrock
(1927) and Chandler (2001a), who also illustrated an adult
male.
Distribution First found in Britain in 1993 but now known
from six sites: Buckingham Palace Garden, Middlesex
before 7 July 1995, Malaise trap); Wheatfen Broad, Norfolk
(10 July 1993, I. Perry); Paradise, Cambridgeshire (19 July
1998, I. Perry); Osier Lake, Godmanchester,
Huntingdonshire (August 1998, J.H. Cole); Coombe Hill
Canal SSSI, Gloucestershire (21 May 1994, C.M. Drake);
Wheldrake Ings SSSI, Yorkshire (17 July 1996, P.J.
Chandler and others).
Habitat Little is known of the requirements of this species.
The known sites are more or less wooded, apart from the
Yorkshire site where adults were numerous in hedges
adjoining water meadows. At Osier Lake it was numerous
in Salix carr. The Norfolk male of C. alternans was found
on foliage of shrubs as rain commenced.
Ecology Biology unknown. This is one of two described
European species of a large mainly tropical genus, with a
second recently described species discovered on Jersey,
Channel Islands and is also known from Switzerland and the
Czech Republic. The latter species (C. loici) could have
been introduced by horticulture as has evidently happened
with the widespread mainly Mediterranean species Leia
arsona Hutson, also recently found to occur in Jersey.
Adults recorded in July.
Status Included in Chandler (1998b) and formally added to
the British list by Chandler (2001a); not listed by Shirt
(1987) or Falk (1991). This is a distinctive species (mainly
yellow with dark abdominal bands and dark ringed
antennae) which could not have been overlooked by earlier
recorders. Its appearance at six widely separated sites in
recent years is therefore difficult to explain.
Threats Uncertain but damage to vegetation structure
possibly significant. The majority of the known sites have
some measure of protection as SSSIs or are otherwise
secure.
Management and conservation Unclear other than to
maintain existing mosaic of vegetation.
Published sources Chandler (2001a).
CORDYLA INSONS
A fungus gnat
Order DIPTERA
Cordyla insons Laštovka & Matile, 1974
DATA DEFICIENT
Family MYCETOPHILIDAE
Identification Described and figured by Laštovka & Matile
(1974).
Distribution Recently found at the King’s Forest, Suffolk
(4 November 2004, I. Perry); otherwise a scatter of records
from the Scottish Highlands: Fealar Gorge, Perthshire
(1999); several sites on the Mar Lodge Estate,
Aberdeenshire (2000); Anagach Woods (2004), Elgin;
Rothiemurchus (1982), Loch an Eilein (1966, 2004),
Abernethy Forest NNR (1978, 1986, 1991, 1999), Loch
Garten (1982) and Glen Coiltie (2001), Easterness; Dam
Wood, East Ross (1991).
Habitat Most sites are ancient Caledonian Pine (Pinus)
forest.
Ecology Biology unknown. Related species have been
reared from terrestrial fungi of the genus Russula. Adults
recorded in June to July and in September; the Suffolk
record was in November.
Status Mainly found in the Scottish Highlands, where it
was apparently overlooked before 1966. Added to the
British list by Chandler (1998b), although Chandler (1987a)
referred to an old unlocalised Irish specimen. This species
belongs to a taxonomic group which requires more study in
Europe. 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 native Pine woods for intensive
forestry or agriculture.
Management and conservation Maintain native woodland
with all successional stages to ensure its continuity. Avoid
damage to leaf litter or soil structure to ensure survival of
fungus hosts which may include mycorrhizal species.
Published sources Chandler (1987a).
DOCOSIA CARBONARIA
A fungus gnat LOWER RISK (Nationally Scarce)
Order DIPTERA
Family MYCETOPHILIDAE
Docosia carbonaria Edwards, 1941
Identification Keyed by Hutson, Ackland & Kidd (1980).
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