first it makes a narrow gallery lined with frass, but subsequently
it makes a series of large translucent yellowish brown blotch mines
from which all frass is ejected. It also constructs under the leaf
an 'aerial' network of silk threads in which it moves around and
rests clear of the leaf surface when not feeding (UKMoths).
mine begins at an egg shell that almost invariably is placed on
(not next to) the midrib. The egg is oval, not globular, like in
the Nepticulidae. Here a narrow tortuous corridor of some 30 mm
begins, with a central frass line, reminding of a Stigmella mine, that often cuts off part of the leaf, causing it to die. Then
the larva leaves this mine and begins to make a series of full depth
full depth mines (not necessarily on the same leaf). The larva is
larger than the mine, and protrudes from it with the rear part of
its body. The openings to all these mines are in the lower epidermis.
Under the leaf an irregular spinning develops, in which frass grains
are trapped. Pupation outside the leaf (Bladmineerders van Europa).
mine is also illustrated in British
Larva: The larvae of moths have a head capsule and chewing mouthparts with opposable mandibles (see video of a gracillarid larva feeding), six thoracic legs and abdominal legs (see examples).
The larva is illustrated in British
and Bladmineerders van Europa.
Pupa: The pupae of moths have visible head appendages, wings and legs which lie in sheaths (see examples).
The pupa is attached to a leaf without a cocoon. It has a dorsal
keel and a pronounced facial beak (UKMoths).
The pupa is also illustrated in British
leafminers and by Patocka (2000a) Bladmineerders van Europa.
The adult is illustrated in UKMoths
and the Encyclopedia
of Life. The male
genitalia are illustrated by the Lepidoptera Dissection Group.
Hosts in Great Britain & Ireland:
of year - larvae: July, August; September (British
of year - adults: Two generations; in August and October to
May, being 'somnolent' in the winter months (UKMoths).
in Great Britain & Ireland: Widespread in southern Britain
including Bedfordshire, Cambridgeshire, Derbyshire, East Norfolk,
East Suffolk, Glamorganshire, Hertfordshire, Isle of Wight, Leicestershire,
Middlesex, North Devon, North Somerset, South Lancashire, South Wiltshire,
Staffordshire, Surrey, Warwickshire, West Cornwall, West Gloucestershire,
West Norfolk, West Suffolk and Worcestershire (NBN
Atlas). Also Suffolk
See also British
leafminers distribution map.
is subject to huge fluctuations in numbers. Before 1998 it had never
been recorded in Chester, but in that year the larvae were found
in over 20 localities the length and breadth of the country. It
was also found then in Denbigh, S. Lancaster and Derby for the first
time. Since then there have been very few sightings in these counties
recorded in the Republic of Ireland (Karsholt and van Nieukerken
in Fauna Europaea). See also Ireland's NBDC interactive map.
elsewhere: Widespread in continental Europe including Austria,
Azores, Belgium, Bosnia and Herzegovina, Bulgaria, Canary Is., Croatia,
Czech Republic, Danish mainland, Estonia, Finland, French mainland,
Germany, Greek mainland, Hungary, Italian mainland, Latvia, Liechtenstein,
Lithuania, Luxembourg, Macedonia, Madeira, Malta, Norwegian mainland,
Poland, Portuguese mainland, Romania, Russia - Central, East and
Northwest, Sardinia, Sicily, Slovakia, Spanish mainland, Sweden,
Switzerland, The Netherlands, Ukraine and Yuogoslavia (Karsholt
and van Nieukerken in Fauna Europaea).
NBN Atlas links to known host species:
British and Irish Parasitoids in Britain and elsewhere: