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

Management and conservation Retain any dead wood and
old or diseased trees, ensuring the continuity of these in the
future; also marshy areas and streams, as well as rides and
clearings in which umbels and other flowers can exist if
these are a requirement.
Published sources Chandler (1992b).
MONOCENTROTA FAVONII
A fungus gnat
VULNERABLE
Order DIPTERA
Family KEROPLATIDAE
Monocentrota favonii Chandler, 1987
Identification Characterised and genitalia figured by
Chandler (1987b).
Distribution Only eight localities known: Rosehaven Cliff,
Cornwall (12 July 2001, P.J. Chandler); Chudleigh Rocks,
(15 August 1978, J.H. Cole) and Higher Knowle (14 July
2001, R.K. Merrifield), Devon; Brenscombe (June 1989,
A.E. Stubbs) and The Spittles (28 June 1998, J.H. Cole),
Dorset; Bramshaw Wood, New Forest, Hampshire (18 July
1995, I. Perry); Dinefwr Deer Park, Carmarthenshire
(Malaise trap 1996); Stackpole Quay, Pembrokeshire (12
July 1986, M.J. Morgan).
Habitat The Welsh example was found at rest on a rock
surface at the base of cliffs beside a beach. Those from
Cornwall, Dorset and one of the Devon sites were also on
coastal cliffs. The other Devon record, however, was from
within woodland on a rocky slope a few miles inland. The
Hampshire and Dinefwr Deer Park records do not appear to
fit this pattern of association with cliffs.
Ecology Biology unknown. The present evidence suggests
that rock crevices may be a larval development site.
Status As this was first published as new to science in
1987, it was not listed by Shirt (1987). It has also been
found in Portugal and France. The occurrence of this
distinctive species only as isolated individuals indicates that
the population size is small and may fluctuate significanlty.
Status revised from RDB 1 (Falk 1991).
Threats Probably the loss of rocky slopes and cliffs through
coastal development or quarrying.
Management and conservation Maintain the presence of
rocky slopes and cliffs, including any associated woodland
and shading vegetation that may be integral to the site.
Published sources Chandler (1987b, 1992b); Howe et al.
(2001); Levey & Pavett (2000a).
NEOPLATYURA BIUMBRATA
A fungus gnat
VULNERABLE
Order DIPTERA
Family KEROPLATIDAE
Neoplatyura biumbrata (Edwards, 1913)
Identification Keyed by Hutson, Ackland & Kidd (1980).
Distribution Mainly recorded from coastal sites in the
south west: Mevagissey (1941) and Padstow (1903),
Cornwall; West Town, Somerset (1928); Studland NNR
(1909) and Wool Heath (20 August 2000, A. Warne),
Dorset; Freshwater, Isle of Wight (1948); New Forest,
Hampshire (1909); Dinas Head, Pembrokeshire (1943). A
record from Tile Hill Reserve, Warwickshire (pre 1940) is
anomalous and requires confirmation (it could be based on a
Macrocera species). It was recorded from Jersey, Channel
Islands by Smith (1958) and has recently been found there
again (Heatherview, St Ouen, 1991; St Laurence Valley,
1994).
Habitat Possibly woodland in some sites but could also be
open habitats including cliff grassland.
Ecology Biology unknown. Larvae may be web forming
predators on terrestrial substrates as are some other
Keroplatinae. Adults recorded in August and September;
October in Jersey.
Status A distinctive species which is evidently very scarce
on the British mainland, with only the single 2000 record
since 1948, suggesting that a decline has occurred. This was
listed in Orfelia by Shirt (1987).
Threats Unclear other than destruction of habitats by
coastal development and the encroachment of intensive
agriculture or forestry.
Management and conservation Unclear other than
maintenance of sites in a natural state with a diverse
vegetation structure and without excessive disturbance.
Published sources Audcent (1929, 1949); Chandler
(1978a); Edwards (1913); Grensted (1944); Hutson,
Ackland & Kidd (1980); Saunt (1940); Smith (1958).
ORFELIA BICOLOR
A fungus gnat
Order DIPTERA
Orfelia bicolor (Macquart, 1826)
DATA DEFICIENT
Family KEROPLATIDAE
Identification Characterised by Chandler (1992b), who
figured the female ovipositor. The male genitalia were
figured by Dziedzicki (1915) and more recently by
Chandler (2001a).
Distribution First recorded as British from a single female:
Magor Marsh SSSI, Monmouthshire (21 July 1988, Holmes,
Boyce and Reed). Males have since been found at three
further sites: Sheffield Bottom, Theale, Berkshire (20 June
and 7 July 2003, P.J. Chandler); Burnham Beeches NNR,
Buckinghamshire (Malaise trap in Beech woodland, 20 July
to 2 August 1995, J.W. Ismay); Hafod Garregog NNR,
Caernarvonshire (30 May – 14 July 1999, B. Levey & M.
Pavett).
Habitat Fen dominated by Carex riparia at the
Monmouthshire site, while the other sites are broad-leaved
woodland. European records indicate associations with dry
grassland and mixed coniferous/deciduous woodland
habitats, similar to the British sites other than Magor Marsh.
Ecology Biology unknown. Larvae may be web forming
predators on terrestrial substrates as are other members of
the genus.
Status Unclear but evidently restricted and local, as only
one individual was found during the extensive Welsh
Peatland Invertebrate Survey by the former NCC, and
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