Vol 10 Part 14. An introduction to the immature stages of British Flies ...

herbaceous garden plants. The main pest species is Tipula paludosa Meigen which
occurs in all soil types (clay, marl, peat, sand). The worst attacks occur in the spring,
especially on young plants of crops sown on freshly ploughed grassland when the
leather jacket population may be as high as hundreds of thousands per acre. Usually
Jeatherjackets feed on roots and underground stems just below the soil surface but on
warm nights they will feed on the surface, cutting off the plants at soil level. Sometimes,
especially after heavy rain, they will be forced up through cracks in concrete, between
paving stones etc and become trapped on the surface in very large numbers on hard
areas into which they cannot burrow, such as paths and concrete surrounds of houses,
and thus be reported as a nuisance.
Brindle (I 967) keys the genera and species of this subfamily. The common 'pest'
species usually found in pasture soil or gardens may be identified as follows.
Dorsum of prothorax with two raised welts (fig. 16). (N. appendiculata (Pierre) ( = maculata
Meigen) is a common garden species) . . . . . Nephrotoma spp.
Dorsum ofprothorax without raised welts (fig. 15). . . . . (Tipula sp.) 2
2 Dorsal pairs (dl) of anal lobes sclerotized to tip (fig. 13) . . . T. vernalis Meigen
Dorsal lobes not sclerotized . . . . . . . . . . . . . . . . . 3
3 Only the lateral pair (lp) of anal papillae elongated, the ventral (vp) being rounded (fig. 10)
. . . . . . . . . . . . . . . . . . . . . T. paludosa Meigen
At least two pairs of elongated, tapering, anal papillae, lateral (lp) and ventral (vp) . 4
4 Pigmented marks between spiracles obvious (fig. 12), pigmented borders of anal lobes
darker, disc whitish yellow, larva yellowish brown in colour, not translucent . . . .
. . . . . . . . . . . . . . . . . . . . T. czizeki De Jong
Pigmented marks between spiracles weak, often absent (fig. 11), pigmented borders of anal
lobes lighter, disc whitish, larva greyish, rather translucent . . . . T. oleracea L.
Cylindrotominae. The four British species of this subfamily have very distinctive
caterpillar-like larvae which feed openly on the leaves of marsh plants.
Diogma glabra/a (Meigen) (fig. 17) is green in colour and occurs in terrestrial mosses,
usually on stones in limestone woodlands; Triogma trisulcata (Schummel) is dark
brown or brownish green and occurs in semi-aquatic mosses (e.g. Hypnum cuspidatum)
on moors; Phalacrocera replicata (L.) (fig. 19) is dark brown, paler below and is found
on aquatic mosses (e.g. Hypnumfluitans or Sphagnum) in acid pools on moors or in
woodlands; Cylindrotoma distinctissima Meigen is light green, darker dorsally and
feeds on the leaves of Caltha, Viola, Stellaria, Anemone, etc.
Brindle ( 1967) keys the British genera and species.
Limoniinae. The larvae of this subfamily can be approximately separated into four
tribes as below.
Brindle ( 1967) keys the British genera and species so far described as larvae and Crisp
& Lloyd (1954) give much useful biological information.
Limoniini - larvae without obvious anal lobes, frequently living in silken tubes,
herbivorous. Larvae occur in wet earth, decaying vegetation immersed in water or
mud, on partly submerged stones in shallow streams, on piles and bridge piers where
they feed on algae. Larvae of Limonia (Geranomyia) unicolor Haliday feed on algae on
marine structures washed by the tide. L. nubeculosa Meigen (fig. 29) is a very common
species beneath leaves in woods. There are 58 British species in 7 genera in this tribe of
which some 25 species of Limonia s. I. are unknown in the larval stage.
Pediciini - larvae with two anal lobes, free living and carnivorous. The larva of
Pedicia rivosa L. (fig. 25) has four pairs of creeping welts or tubercles which lack ventral
hook-like spines at the tip. It is fairly common is aquatic or semi-aquatic mosses or in
decaying vegetation in boggy places near streams and springs, where it feeds mainly
on Diptera larvae (e.g. Chironomidae, Ceratopogonidae). Another common species
Dicranota bimaculata Schummel has 5 pairs of well developed ventral pseudopods,
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