Key for the identification of the known mines of British
insects (Diptera and non-Diptera) recorded on Vaccinium
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1a > Leaf-miner and case-bearer: The larva lives outside the mine, protected by a case, and feeds on the underlying plant tissues via a hole cut in the epidermis. From that point it eats away as much leaf tissue as it can reach without fully entering the mine. Mine does not contain frass (Coleophora species) |
2 |
1b > Leaf-miner, but not a case-bearer: The larva lives mainly inside the mine. Mine usually contains frass. In later instars the larva may live sandwiched between two more or less circular sections cut from the leaf. |
3 |
2a > Leaf-miner
and case-bearer:
The full-grown larva in a bivalved composite leaf case, composed of three leaf fragments of increasing age and decreasing size; the case measures c. 10 mm, the mouth angle is c. 60°.
Has a two year life cycle and ultimately forms a case of three pieces of mined leaf (British leafminers) |
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On Vaccinium in Britain and elsewhere. Britain including
Easterness and South Aberdeen. Widespread in continental Europe.
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Coleophora
idaeella Hofmann, 1869 [Lepidoptera: Coleophoridae]. |
2b > Leaf-miner
and case-bearer: A complex life cycle with the larvae initially mining the leaves,
before forming a small case in the autumn of the year. The final
case is 6-8 mm long and the feeding signs are very visible with
the larva being able to leave its case and enter the leaf to feed.
The
larva begins by making a frass-filled corridor of about 1 cm length;
then the corridor widens into a blotch. The larva then cuts an elongated
piece of epidermis out out the upper and lower epidermis of this
blotch and uses it to construct its first case. In first case (elsewhere
already in the mine) it passes its first winter. After hibernation
it makes a new case in the same way, and later, after another hibernation,
a third one. The case of the full-grown larva is a spathulate leaf
case of 6-8 mm, composed of two elongates pieces of epidermis. The
case is straight; the rear end is somewhat pointed and bivalved.
The mouth angle is 90°. The full depth mines that are made by glitzella often occupy half a leaf, and may contain some
frass grains. This is because the lava, after having secured its
case with silk on the leaf, often leaves the case altogether and
may immerse itself deeply in the mine. |
Case
of Coleophora glitzella on Vaccinium vitis-idaea
Image: © Duncan Williams (British
leafminers) |
On Vaccinium in Britain and elsewhere. Britain including
Banff, East Perth, East Ross, Easterness, Elgin and Mid Perth.
Widespread in continental Europe.
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Coleophora
glitzella Hofmann, 1869 [Lepidoptera: Coleophoridae]. |
2c > Leaf-miner
and case-bearer: The fully developed larval case, 6 mm long, on cowberry, in April
and May of its second year of life, is easily identified by its
structure of about forty discs of leaf arranged like a pile of coins,
its walking stick shape and the ventral keel of white silk. Each
larva makes a large number of small full depth mines, which can
be recognised by the relatively large hole where a disc of leaf
has been excised for the case.
Greyish
black tubular composite leaf case of about 5-6 mm. The case is composed
of numerous rings, each cut out of the lower epidermis of the hostplant.
The rear end is stromgly curved, like the handle of a walking stick.
Mouth angle 45°. |
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On Vaccinium in Britain and Vaccinium and Pyrola elsewhere. Occurs on the more sheltered parts of moors and Scots
pine woodland in the Highlands of Scotland, the Pennine Hills
and the Clwyd Hills. Widespread in continental Europe.
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Coleophora
vitisella Gregson, 1856 [Lepidoptera: Coleophoridae]. |
3a > Leaf-miner: The young larvae hatch in around August and form a narrow gallery
mine in the leaves of cowberry, eventually turning into a blotch
in the centre of the leaf, where it pupates in an inflated cavity.
Oviposition
at the underside of the leaf. The mine begins as a long corridor,
with the frass in a broad central line, leaving a clear margin at
either side. This gallery abruptly widens into a large full depth
blotch, with a central concentration of frass. The full-grown larva
makes an exit slit in the lower epidermis, then spins an orange-yellow cocoon within the
mine, that is connected with the exit by
a silken tunnel. The cocoon causes the leaf to pucker blister-like. |
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On Vaccinium in Britain and elsewhere. A submontane species,
occurring on high moorland and mountains in Wales, northern England
and northern Scotland. Widespread in continental Europe.
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Fomoria weaveri (Stainton, 1855) [Lepidoptera: Nepticulidae]. |
3b > Leaf-miner: The larvae mine leaves at first, forming a blotch mine, later descending
to the ground in a portable case and feeding on dead leaves.
Oviposition
is by way of an ovipositor, therefore no egg shell visible. The
larva makes a small, roundish, blotch; often several in a leaf.
Already after its first moult it makes an excision out of the mine,
in size almost equal to the blotch (3-4 mm). Thus sandwiched it
drops to the ground and continues feeding on dead leaf material. |
Mines
of Incurvaria masculella
Image: © Rob Edmunds (British
leafminers) |
On Crataegus and Rosa, but not yet on Vaccinium,
in Britain and Carpinus, Corylus, Vaccinium, Catanea, Fagus,
Quercus, Crataegus, Rosa and Tilia elsewhere. Widespread
in Britain, Ireland and continental Europe.
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Incurvaria
masculella (Denis & Schiffermüller, 1775) [Lepidoptera:
Incurvariidae]. |
3c > Leaf-miner: Oviposition by way of an ovipositor, no egg visible therefore.
The larva makes an irregular blotch. The part of the mine nearest
to the oviposition site is more thranslucent than the later, in
transparancy more greenish, part of the mine. The mine usually lies
close to the leaf tip, often several together. After its first moult
the larva makes a roundish excision, 3-4 mm in diameter. Incurvaria larvae, while resting, take a horse-shoe like posture, unlike the larvae of Antispila species. Sandwiched herein it drops to the ground and continues feeding of dead leaves.
The excision occupies about half of the surface of the blotch.
The
mine is also described in. |
On Vaccinium myrtillus, Prunus and Rubus chamaemorus in Britain. On several genera and species of several
plant families, including Prunus, elsewhere. Widespread
in much of the British Isles and continental Europe.
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Incurvaria
oehlmanniella (Hübner,
1796) [Lepidoptera: Incurvariidae]. |
3d > Leaf-miner: The mine on the underside can cause the whole leaf to arch.
Mines
are most often found on plants low down amongst the heather.
Lower-surface
tentiform mine, that involves almost the entire leaf. The leaf margins
are strongly pulled together, arching the upper surface. Because
the leaf tissue of the roof of the mine is incompletely eaten away,
this upper surface has got a mottled appearance. |
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On Vaccinium in Britain and elsewhere. A species of higher
ground, particularly moorland. Widespread in continental
Europe.
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Phyllonorycter
junoniella (Zeller, 1846) [Lepidoptera: Gracillariidae]. |
3e > Leaf-miner: A contorted gallery leading to small blotch.
Ovipostion
at the leaf underside, usually near the midrib. Mine a contorted
gallery, often a secondary blotch. Leaf around the mine often turns
purple. Frass in a thick central line. Pupation external.. |
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On Vaccinium in Britain and elsewhere. A relatively local
species, but hard to find and probably overlooked in many places
due to its upland bias. It has been found in England, Wales and
Scotland, but is scarce in the south-east. Widespread in continental
Europe.
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Stigmella
myrtillella (Stainton, 1857) [Lepidoptera: Nepticulidae]. |
3f> Leaf-miner: The larva nitially forms mines in the leaf with plentiful dispersed frass. It then leaves the mine and feeds on spun leaves by eating the upper epidermis and parenchyma (see British leafminers). |
Local and found on hills and mountainsides. |
Rhopobota ustomaculana (Curtis, 1831) [Lepidoptera: Tortricidae]. |