Three
species of Betula are native to Britain - Dwarf Birch (B.
nana), Silver Birch (B. pendula) and Downy Birch (B.
pubescens). Paper birch (B. papyrifera) has been introduced.
Only
one Diptera miner, the agromyzid Agromyza
alnibetulae, is recorded on Betula in Britain.
Fifty-six
non-Diptera miners are recorded on Betula in Britain (see
below).
Dickerson
provides keys to the most of the mines of Lepidoptera: Bucculatricidae,
Eriocraniidae, Incurvariidae, Heliozelidae, Lyonetiidae, Nepticulidae
and Gracillariidae recorded on Betula in Britain (British
leafminers).
Silver
Birch Betula pendula
Elsewhere
eight additional British non-Diptera miners are recorded on Betula
(see below).
The
yponomeutid Swammerdamia
passerella is recorded spinning the leaves of Betula
and feeding on the leaf surface.
N.B.
The key to mines below includes mines recorded on Betula
and Carpinus (Betulaceae).
Key
for the identification of the known Diptera mines on Betula and Carpinus in Great Britain and Ireland
1>
Larva forming a narrow, unusually long, upper surface leaf mine
up to 12 cms, sometimes considerably widening at end; young leaves
are frequently distorted. Puparium reddish-brown
Leaf-miner
and case-bearer:
Larva mines leaves in autumn. Spring feeding is by grazing,
usually on the underside of larger leaves, or feeding on
the edges of small leaves. The full-grown case is black,
pistol-shaped, 7 mm long (British
leafminers), rather like the closely related C.
ibipennella, which feeds on oak. Indeed, at one
time they were believed to be conspecific (UKMoths).
Prior to hibernation the young larva makes full depth mines;
in spring window feeding takes place. In its final stage
the larva lives in a matt pistol case about 7 mm in length,
that with a mouth angle of 30°-45° is standing obliquely
on the leaf (Bladmineerders
van Europa).
Leaf-miner
and case-bearer:
Larva mines leaves. The case is enlarged several times by
mining a leaf-edge and inserting the existing case into
the mine which is joined with silk. The final case is 7-8
mm long (British
leafminers).
Larva
in a composite leaf case, composed of large leaf fragments.
Characteristically, the leaf fragments are attached in a
failry untidy way. In spring the case has two colours, because
the old material (dull yellowish, grey or pink) dates from
before the hibernation, while new, reddish brown material
dates from after the winter. The case finally is about 7-8
mm long; the mouth angle is 40-45°. (Bladmineerders
van Europa).
Leaf-miner
and case-bearer:
Lobe case. Many small leaf fragmnts are attached to the
tubular case; its end is strongly curved downwards. The
larvae are attched to the leaf underside, where they make
a large number of relatively small full depth mines (Bladmineerders
van Europa).
Mines
of Coleophora fuscocuprella on Corylus avellana
Image: Willem Ellis (Bladmineerders
van Europa)
Leaf-miner
and case-bearer: As with other Coleophorids, the larva
forms a case from the leaf, in which it overwinters. The
case formed by this species is long, slender and frequently
woolly in appearance (UKMoths).
Bivalved
composite leaf case of 8-10 mm, rather strongly compressed
and keeled, with a mouth angle of 30-45° (Bladmineerders
van Europa).
Case
of Coleophora lusciniaepennella on Salix babylonica
Image: Willem Ellis (Bladmineerders
van Europa)
Leaf-miner
and case-bearer:
Larva mining leaves, the blotches brownish. The final case
is 8-11 mm long, slender, and fixed at 45° to leaf surface,
with anal end laterally compressed. The case has a serrated
keel due to formation from the edge of a leaf (British
leafminers).
Spatulate
leaf case. Strikingly slender, bivalved case, 8-11 mm long,
with a slight curve at the rear end, that is keeled and
often toothed. The end is laterally compressed. Mouth angle
45°. The full depth mines often are conspicuously brown (Bladmineerders
van Europa).
Leaf-miner
and case-bearer:
Composite leaf case. The material used to enlarge the case
consists of large pieces of full depth mine, that are attached
with such precision that they may seem seemless. In the
course of summer an autumn two (sometimes three, according
to Hering, 1927b) pieces are added. No more material is
added after hibernation, causing the case in spring to be
rather uniformly coloured (contrary to C. binderella,
that does add an extension in spring, and is made of fresh
leaf material) (Bladmineerders
van Europa).
Leaf-miner
and case-bearer:
The case resembles that of C.
violacea, but does not lie so flat again the leaf
as this species (having a mouth angle of 30 to 50°).
C. violacea
also has a case which bulges in the middle, whereas in C.
potentillae the case tapers towards the posterior (British
leafminers).
Immediately
after emergence the larva makes a full depth, quickly widening,
corridor, with frass as small grains in a broad central
band. Finally results a blotch of 2 x 5 mm, from which the
youth case is cut. The fully developed case is a hairy,
greyish brown to silver grey lobe case of about 1 cm long,
with a clearly laterlly compressed end; the mouth angle
is about 90°. The case is difficult to separate from
the one of C. ochripennella (Bladmineerders
van Europa).
Mines
of Coleophora potentillae on Sanguisorba minor
Image: Willem Ellis (Bladmineerders
van Europa)
Leaf-miner
and case-bearer:
The larva feeds by inserting its head into small mines it
creates on the leaves of birch, elm, alder, or hazel. Occasionally
it is found feeding on other trees, or on herbaceous plants
onto which it has accidentally fallen. It forms two cases
during its larval life. The first case is initially curved,
smooth, laterally compressed with a bivalved anal opening,
and about 2 mm long in September. During October it feeds,
and adds a few rough collars of larval material around the
oral opening. After hibernation, it feeds again in April
and early May, adding more protruding collars until they
equal or exceed the original smooth part of the case. At
the same time, it expands the case girth by the creation
of a silk gusset ventrally. The second case, 6 or 7 mm long,
is formed in May, leaving the vacated first case attached
to its last feeding mine. The new case is tubular with a
trivalved crimp at the anal opening. The dorsum is formed
from the edge of the leaf from which the case was cut. This
results in a more or less serrated dorsal keel, depending
on the plant species and the individual piece of leaf used.
Considerable variation in the degree of serration can be
found, even among specimens off the same tree. The case
colour varies with food plant, from yellowish brown on birch,
darkening through elm and hazel to dark brown on alder (UKMoths).
The
strongly curved young case is is a composite leaf case,
the adult case is a tubular leaf case. The adult case is
bivalved, about 7 mm in length; the mouth angle is around
30°. The case is straw coloured and almost always has
a toothed dorsal keel (remnant of the margin of the leaf
from which the case was cut). Neither larvae or cases of
C. coracipennella,
prunifoliae,
serratela and spinella
can be separated; from serratella (Bladmineerders
van Europa).
Leaf-miner
and case-bearer:
Tubular leaf case. The case is almost barrel-shaped, with
a large leaf fragment that, while withering, folds itself
untidily arround the tube (Bladmineerders
van Europa).
Leaf-miner
and case-bearer:
The larva feeds on a wide range of trees, shrubs and herbs,
favouring Rosaceae, but not exclusively. The fully developed
cased larva may be found active in October and again, after
winter diapause, in April. Cases, about 6 mm, of diapausing
larvae may be found through winter, fixed to a tree or fence
post. The dorsal surface of the case is usually covered
in leaf fragments, but they can sometimes be worn off almost
smooth. The ventral surface is swollen at the middle and
has a keel, which usually bends upwards at the posterior.
The cases of C.
ahenella (on Rhamnus, Frangula, Viburnum
and Cornus) and C.
potentillae (case less swollen, keel not bent up,
resting position less prone) are very similar (UKMoths).
Brownish
lobe case that lies almost flat on the leaf, either on the
upper or on the lower side. Case widest about the middle.
Ventrally there is a distinct keel. Mouth angle 0°.
Full depth mines rather large. The flaps of cuticular tissue
that serve to enlarge the case are cut out of the upper
epidermis. (contrary to C.
ahenella and C.
potentillae, that use tissue from the lower epidermis).
The removal of these tissue flaps creates holes that are
much larger than those that serve as the entrance to the
mine (Bladmineerders
van Europa).
Leaf-mine:
Long, full depth mine, starting at an oviposition scar,
mostly in the distal part of the midrib; the scar may be
swollen and gall-like. Frass line variable in width, sometimes
quite broad. Usually the corridor loosely follows the leaf
margin, and the part of the leaf that is cut off from the
centre dies off. The larvae live in spring, when the leaf
is unfolding; later in summer affected leaves are recognisable
because the tip of the leaf and parts of the marginal teeth
are missing, by remnants of the corridor and by a general
disfiguring of the leaf. The larva leaves the mine before
pupation (Bladmineerders
van Europa).
Leaf-mine:
A rather stubby, gradually widening, corridor that usually
begins near the leaf tip and descends along the leaf margin
(especially in the first generation). Finally an almost
perfectly circular excision is cut, in which the larva drops
to the ground for pupation (Bladmineerders
van Europa).
Leaf-mine:
Oviposition in the underside of the midrib or a thick lateral
vein; later a large scar is visible there. Initially the
larva tunnels in the midrib or vein, that inflates and disfigures
somewhat as a result. Then the larva starts a corridor in
the leaf blade, quite narrow at first, but strongly widening
as the larva approaches the leaf margin or leaf tip. The
mine is reddish brown in colour. The mature larva makes
itself a dark brown globular cocoon in the mine and pupates
there. Because the mine is made at a time that the leaf
still is unfolding, the leaf becomes permanently rumpled.
In the course of the summer the mine erodes away, but the
combination of the oviposition scar, the swolllen mibrib
and the frayed leave missing a large part of its distal
half remains unmistakable (Bladmineerders
van Europa, as testaceus).
Leaf-mine:
Generally small, upper-surface, pear-shaped mines, half
of their surface stuffed with frass. In the frass-free part
an oval, flattened larva. Often several mines in a leaf.
Prior to oviposition the larvae eat, a large number of tiny
holes in the leaves (Bladmineerders
van Europa).
Leaf-mine:
Full depth corridor, beginning at the base of the midrib
and very roughly following the leaf margin; all the while
the corridor widens, until almost the entire leaf has been
mined out. Frass, as coarse grains or thread fragments,
in the centre of the mine. The larva pupates in the mine,
in a globular cocoon made of secretion (Bladmineerders
van Europa).
Leaf-mine:
Oviposition in the base of the midrib, without giving rise
to an oviposition scar. The larva initially bores inside
the midrib. Later it leaves the midrib, forming a broad
corridor in the blade, that widens into a blotch. Finally
the legless larva pupates in a globular cocoon inside the
mine. Because the mine develops at a time that the leaf
is fully developed, mined leaves are not disfigured (Bladmineerders
van Europa).
Leaf
mine: A
rather large, clear, partly full depth blotch that begins
in the axil of a thick lateral vein. Often the ovipostion
leaves a greyish-green scar. Generally several mines in
a leaf. The mine expands within the confines of the midrib
and two lateral veins; only close to the leaf margin, where
the lateral veins are thin, the mine may trespass over a
vein (Bladmineerders
van Europa).
Leaf
mine:
Large blotch, starting from the leaf margin. The very first
triangular part of the mine is filled with a dense mass
of frass, caused by lateral movements of the larva that
actually press the frass in this first mine segment. The
mine seems full depth, but actually is upper-surface, abeit
very deep and (fresh) only very weakly greenish. Pupation
outside the mine (Bladmineerders
van Europa).
Leaf
mine: Large blotch, begining at the leaf margin (there
is no accumulation of frass). The oldest part of the mine
with a charcteristic, wine red colour. Most of the frass
is ejected through a narrow slit in the leaf margin. The
larva makes an discoidal cocoon within the mine. Hibernation
in the larval stage
(Bladmineerders van Europa).
Leaf
mine:
Blotch, starting in the centre of the leaf. An ill-defined
accumulation of frass in its first part. The blotch develops
with little consideration of the major veins. Several mines
may occur in a leaf, and coalesce into one large blister
(Bladmineerders
van Europa).
Leaf
mine:
Large, transparent, in fresh condition pale green blotch
that begins at the leaf margin, without an accumulation
of frass. Mine and larva are undistinguishable from those
of S. vicina,
but vicina larvae live from mid May till mid June,
while the larvae of betuleti are found only in August
- October (Bladmineerders
van Europa).
Leaf
mine:
Large, transparent, in fresh condition pale green blotch
that begins at the leaf margin, without an accumulation
of frass. Mine and larva are undistinguishable from those
of S. vicina,
but vicina larvae live from mid May till mid June,
while the larvae of betuleti are found only in August
- October (Bladmineerders
van Europa).
Leaf-mine:
The
larva begins with a short, full depth corridor, often along
the midrib or a thick vein. Most of the mine with a thick
frass line. The larva soon leaves the mine, and starts causing
window-feeding, later eating holes in the leaf. The larval
chamber (the space occuped by the larve, while in the mine,
obviously free of frass) is more than three times as long
as wide (Bladmineerders
van Europa).
Leaf-mine:
The
larva mining the leaves initially and then living inside
a rolled leaf in later instars (UKMoths).
The
mine starts with an unconspicuous epidermal corridor, mainly
visible by a reddish brown frass line. During the following
larval stage a blotch is formed, that quickly develops into
a tentiform mine; the epidermis is brown. Generally the
mine is lower-surface, but upper-surface mines are not rare.
Frass in a mass of grains in a corner of the mine. After
having left its mine the larva moves twice. First it lives
in a rolled (sometimes just folded) leaf margin, after that
in a leaf that is transverely rolled downwards, starting
from the leaf tip (Bladmineerders
van Europa).
Leaf-mine:
Blotch clouded, with some green matter left in mine.
Several larvae (2-4) in one mine (British
leafminers).
Large
full depth blotch, adjacent to the leaf margin. The mine
is not completely eaten out, which gives it a greenish or
off-white appearance. Frass in threads, that seem to be
somewhat shorter than in other Eriocrania's. The
mine harbours 2-4 strikingly hyaline larvae. Pupation in
the ground. Older mines wither and wear off; in summer no
trace of them is left (Bladmineerders
van Europa).
Mine
of Eriocrania cicatricella on Betula
Image: Ian Kimber (British
leafminers)
Leaf-mine:
The early gallery starts in the centre of the leaf.
It is a linear track which widens to a large blotch at the
leaf edge, with frass in long threads (British
leafminers).
Corridor,
generally beginning in the neighbourhood of the midrib,
rather gradually widening into a very large blotch. Frass
in long threads. Pupation in the ground (Bladmineerders
van Europa).
Leaf-mine:
A blotch with large dark grey larva - discarded grey
larval skin visible in vacated mine. The mine starts by
the edge of the leaf (British
leafminers).
Large,
white, primary, full depth blotch, following upon a very
short corridor. The blotch begins adjacent to the leaf margin,
expanding deeper into the leaf. Frass in striking, long
threads. Pupation in the soil. Vacated mines shrivel and
wither away; later in summer no a trace remains (Bladmineerders
van Europa).
Leaf-mine:
The larva mines in a birch leaf, forming a large blotch
(UKMoths)
starting at or near the leaf edge and then widens into a
blotch (British
leafminers).
Oviposition
a few mm from the leaf margin; here begins a corridor of
some mm, filled with granular frass. This corridor suddenly
widens into a large full depth white bloth, with frass in
long threads. The blotch remains adjacent to the leaf margin,
and often engulfs the initial corridor. Almost always one
larva in the mine (unless by coalescence of two mines).
Pupation external. Older mines wither and desintegrate,
and cannot be found later in the summer (Bladmineerders
van Europa).
Mine
of Eriocrania semipurpurella on Betula pubescens
Image: Willem Ellis (Bladmineerders
van Europa)
Leaf-mine:
A linear track widens to blotch, frass in long threads (British
leafminers).
Corridor,
generally starting not far from the midrib, at a conspicuous,
yellowish oviposition scar, suddenly and somewhat angular
widening into a full depth blotch. Often the corridor is
overtaken by the blotch, but it remains recognisable in
the frass pattern. Frass in long threads. Pupation in the
ground (Bladmineerders
van Europa).
Leaf-mine:
The mine starts at or near the leaf edge and widens
to a blotch with frass in long threads (British
leafminers).
Large,
white, full depth blotch along the leaf margin. Frass in
long threads. Old mines wither and disintegrate, and cannot
be found any more later in the summer (Bladmineerders
van Europa).
Mine
of Heringocrania unimaculella on Betula
Image: John Langmaid (British
leafminers)
Leaf-mine:
A
small Phyllonorycter-like mine initially, but with
brown rather than green lower epidermis. Later in one or
more successive cones formed by folding downwards the edge
or tip of a leaf (British
leafminers).
The
mine begins as an inconspicuous lower surface corridor,
mainly recognisable by its brown line of frass. In the next
larval stage a lower-surface blotch is made, that soon develops
into a tentiform mine; its epidermis turns brown. Frass
in a clump in a corner of the mine. After leaving the mine
the larva continues feeding in a downwards folded leaf margin,
that is fixed with silk (Bladmineerders
van Europa).
Leaf-mine:
A small mine (about 1cm long), which strongly arches
the leaf. The mine of Parornix betulae can appear
similar, but the underside becomes brown whereas the mine
of P. anderidae stays green (British
leafminers).
Small
lower-surface tentiform mine; epidermis pale green, rather
weakly folded. The pupa lies without a cocoon in the mine
(Bladmineerders
van Europa).
Mine
of Phyllonorycter anderidae on Betula pubescens
Image: Willem Ellis (Bladmineerders
van Europa)
Leaf-mine:
The mine is in the upper epidermis of a leaf, usually over
midrib or vein. The mine is at first silvery, later with
brown speckling (British
leafminers).
Silvery,
upper-surface, epidermal tentiform mine, centered over the
midrib or a heavy lateral vein. Unlike P.
leucographella, with which this species shares some
host plants, the upper epidermis looks dirty by the presence
of numerous fine black-brown specks of frass. The epidermis
remains without folds until the mine becomes strongly contrated.
Young mines look like a streak of silver on top of a vein
(Bladmineerders
van Europa).
Mine
of Phyllonorycter corylifoliella on Crataegus
monogyna
Image: Willem Ellis (Bladmineerders
van Europa)
Leaf-mine:
The mine is oval on Q. ilex (note - there may
be several mines in the leaf), and similar to P.
quercifoliella on deciduous oaks. It is between
adjacent veins on beech and hornbeam (British
leafminers).
Small,
oval, lower-surface tentiform mine, 9-14 mm long, mostly
between two lateral veins. The lower epidermis with a single
sharp fold (sometimes forked near its end). Pupa in very
flimsy cocoon, that contains a bit of frass laterally and
at the rear end (Bladmineerders
van Europa).
Mine
of Phyllonorycter messaniella on Carpinus
betulus
Image: Willem Ellis (Bladmineerders
van Europa)
Leaf-mine:
The larva forms a blotch mine on the underside of a leaf,
often quite small, but puckering the leaf noticeably (UKMoths).
The
mine is 10-15 mm long, 1-6 creases in lower epidermis (British
leafminers).
Small
lower surface tentiform mine; the lower epidermis is greenish
yellow and weakly folded. Pupation within the mine in a
cocoon that in the summer generation is so flimsy that sometimes
it seems to be missing, while in the autumn generation it
is quite tough. All frass in a corner of the mine (Bladmineerders
van Europa).
Mines
of Phyllonorycter ulmifoliella on Betula pubescens
Image: Willem Ellis (Bladmineerders
van Europa)
Leaf-mine:
The mine in the petiole and midrib leads to an oval
blotch, then a cut-out in leaf-blade (British
leafminers).
The
larva begins its life as a borer in the pith of a twig.
Only when it is almost full grown it enters a petiole, then
the midrib, of a leaf. The leaf becomes starved that way,
and turns somehwat pale. From the midrib a short full depth
corridor runs into the blade, generally in the basal part
of the leaf. The corridor usually is quite short but when
it happens to be longer a central frass line is visible.
Finally an oval excision of about 3 x 5 mm is cut out, in
which the larva drops to the ground (Bladmineerders
van Europa).
Leaf-mine:
The larva starts making a corridor of a few mm, followed,
and mostly overrun, by a circular blotch of 4-5 mm diameter
(Bladmineerders
van Europa).
Generally
several larvae feed in a single leaf, creating a distinctive
pattern of feeding windows. The larvae then cut out circular
cases and drop to the leaf-litter to continue feeding, leaving
behind a leaf containing many circular or oval cut-outs
(UKMoths).
Leaf-mine:
The larva mines young leaves and the narrow initial
mine ends in a blotch. The larva cuts out a section of the
leaf and over winters in this on the ground (British
leafminers).
Long,
very narrow corridor that may wind several times through
the leaf, freely crossing the midrib. The corridor often
cuts off parts of the leaf, that die as a result. The corridor
does not increase in width, until it abruptly widens into
an irregular elongate blotch. In the end of the blotch an
oval excision is made, c. 4 mm long, in which the larva
drops to the ground for pupation. Mines in the very youngest
leaves (Bladmineerders
van Europa).
Leaf-mine:
A long, whitish smoothly-curved upper-surface mine with
broken black frass (British
leafminers).
Oviposition
is by means of an ovipositor; what remains is a small scar:
no egg shell is visible at the start of the mine. From here
a long, sometimes very long, slender, full depth corridor
winds throught the leaf, not steered by leaf margin or the
leaf venation. The midrib is crossed effortless (see 'special');
the corridor frequently also crosses itself; the section
of the leaf cut off then usally turns brown and dies off.
Frass in a narrow central line. The larva vacates the mine
prior to pupation through an exit in the upper epidermis.
Pupation takes place in a cocoon that hangs in a 'hammock'
in a fold of the leaf. The vacated larval chamber is proportionally
much longer than in the case of Stigmella mines (>
3 x longer than broad) (Bladmineerders
van Europa).
Leaf-mine:
The larva mines the leaves of various roseaceous trees,
such as blackthorn and apple, forming a gallery leading
to a blotch (UKMoths).
Eggs
are deposited in the underside of a leaf, well away from
the margin, often several per leaf. Around the oviposition
site a cavity develops that in the end often leaves a hole
in the leaf. Then a narrow, hardly widening, winding corridor,
largely filled with a broad reddish brown frass line. The
corridor abruptly widens into a wide, full depth blotch,
that often lies against the leaf margin. The larva may leave
its mine and continue elsewere, even on a different leaf.
Note that the first blotch may already lie on a different
leaf. Frass dispersed, in oval granules. Most frass is ejected
through semicircular cuts along the outer limit of the blotch;
part of it is often trapped in strands of silk under the
leaf (Bladmineerders
van Europa).
Leaf-mine:
A broad intial mine from tip to base of leaf, which
later contracts. It then folds the leaf edge, later it rolls
the whole leaf longitudinally. Compare with C.
betulicola, which rolls the leaf transversally (British
leafminers).
At
first the mine is epidermal and rather large, sometimes
even occupying the entire length of the leaf. At a later
stage the larva begins to consume the tissue below the epidermis,
and the mine becomes a tentiform one; the leaf is strongly
contracted by then. The epidermis is brown. The mine may
be lower-surface or upper-surface. After the mine has been
vacated the larva moves twice. At first it lives in a rolled,
sometimes just folded, leaf margin, next in a leaf that
has been rolled lengthwise. Pupation in a cocoon at the
underside of a leaf (Bladmineerders
van Europa).
Despite
the scientific name, the larvae feed on birch leaves (UKMoths).
Leaf-mine:
Initially
a lower epidermal gallery which leads to a blotch at the
leaf-edge. Subsequently creates two or three cones by folding
the edge or tip of a leaf downwards (British
leafminers).
The
mine begins with an unusually long lower-surface epidermal
corridor that often follows the midrib for some distance,
but finally turns towards the leaf margin, where a small
blotch is made of up to 1 cm in diameter. The blotch initially
is fully epidermal, but later the larva starts consuming
parenchyma, silk is deposited, and the blotch begins to
develop into a somewhat contracted tentiform mine. In the
end the mine is vacated and the larve continues living freely
under a leaf fold that has been fixed with silk, or in a
leaf tip that has been turned into a cone. Pupation in a
shiny cocoon at the underside of the leaf (Bladmineerders
van Europa).
Leaf-mine:
The mine begins as a contorted gallery, when the young larva
can be seen to have dark plates on each segment. These plates
are later lost and the gallery becomes a blotch with scattered
frass (UKMoths).
Mine
begins at a globular, black, lower-surface egg shell. From
there starts a short tortuous corridor, that widens into
a blotch, often between to lateral veins. Frass dispersed.
Pupation outside the mine (Bladmineerders
van Europa).
Leaf-mine:
The
larvae mine the leaves of birch, creating a distinctive
mine which begins as a dark circular blotch, and is then
extended into a larger pale blotch with a darker central
circle. Sometimes several mines are found in one leaf (UKMoths).
Egg
usually at the underside of the leaf. The mine is a roundish,
often almost circular, primary, upper-surface blotch without
a trace of an initial corridor; often several mines in leaf.
The mine has a conspicuous dark centre, where the larva
often retreats. Young mines consist of only the dark centre,
without the light periphery. Also the frass is accumulated
here; unlike in Leucoptera
malifoliella the frass is not draped in arcs around
the centre (Bladmineerders
van Europa).
Leaf-mine:
A
narrow gallery with frass in thin central line. The moths
must be bred through to distinguish S.alnetella and
S.glutinosae
(British
leafminers).
Ovipostion
at the leaf lower surface. Then a full depth slender, corridor,
often following a vein or the leaf margin for some distance.
Frass in a continuous central line that nowhere is wider
than one third of the corridor width. Frass never coiled.
Usually only one mine in a leaf. Pupation outside the mine
(Bladmineerders
van Europa).
Leaf-mine:
The mine is short, with frass irregular, linear. The larva
is yellow, gut-line green, and dark ventral spots. There
are often several mines in a leaf. The mines are found frequently
on seedlings and small plants (British
leafminers).
Egg
at the underside of the leaf, close to a vein. The mine
is a little widening, rather short, tortuous corridor. The
first part does not encircle the egg, neither is it lower-surface.The
frass line is one third to one half of the width of the
corridor. The sides of the corridor are smooth, not scalloped
out. Mostly several mines in a leaf, not infrequently crossing
each other. Pupation external, exit slit in the lower epidermis
(Bladmineerders
van Europa).
Egg at the underside of the leaf, close to a vein. The mine
is a very long and slneder gallery, hardly widening at all.
Frass in a continuous, very narrow central line. The corridor
follows veins over long distances, obtaining thereby an
angular appearance (Bladmineerders
van Europa).
Leaf-mine:
The mine starts from brown spot, later filled with greenish
frass. The mine is difficult to locate initially but becomes
brown as it ages (British
leafminers).
Egg
at the underside, often in a vein axil. The mine is a slender,
little widening corridor. Its first part is strongly contorted;
the leaf tissue that is cut off thereby is killed, mostly
resulting in a brown spot. The remainder of the corridor
in contrast is very little contorted, often remarkably straight,
when it runs alongside a vein. The corridor is almost completely
filled with coiled frass, that is green when fresh, brown
later. Pupation external (Bladmineerders
van Europa).
Leaf-mine:
The early gallery is filled with frass, later leaving
clear margins (British
leafminers).
Like
Stigmella
microtheriella the larva feeds on hazel or hornbeam,
and its mines are often found alongside that species in
the same leaf. However the mines of S. floslactella
are generally wider, less angular and contain more scattered
frass than those of S. microtheriella (UKMoths).
Oviposition
at the underside of the leaf, in a vein axil. Mine a slender,
gradually widening corridor; the last section is clearly
wider than the larva. In the first section the vaguely delimited
frass line almost fills the corridor. Later the frass lies
in irregular arcs and clouds, filling about one third of
the width of the corridor. The trajectory of the mine is
not angular, independent of the leaf venation. Pupation
external, exit slit in the upper epidermis (Bladmineerders
van Europa).
Leaf-mine:
The mine is long, filled with green frass to ¼, then
linear (British
leafminers).
Oviposition
generally at the underside of the leaf. The mine is a slender
corridor that hardly widens, even towards the end. The first
third is stuffed with diffuse greenish brown frass. After
a moult the frass pattern changes completely, into a very
narrow, continuous black line. The mine often follows a
thick vein over a long distance, but the larva is capable
of crossing thick veins, even the midrib (Bladmineerders
van Europa).
Leaf-mine:
The mine is contorted, starting underside, frass linear
(British
leafminers).
Egg
at the underside of the leaf, mostly close to a vein. The
mine is a fairly slender corridor that even towards the
end hardly widens. The first part consists of a some close
loops around the oviposition site; this part generally is
lower-surface. The later part is much less contorted, with
a frass line that occupies one third to one half the width
of the gallery. The sides of the corridor are irregularly
scalloped out. Usually no more than one mine per leaf. Pupation
external, exit slit in the lower epidermis (Bladmineerders
van Europa).
Leaf-mine:
The frass is brown and in arcs, with narrow clear margins
(unlike continuella
where the green frass completely fills the gallery) (British
leafminers).
Oviposition
on the underside of the leaf. Then a rather slender gallery,
hardly widening, even towards the end. The corridor is not
strongly contorted, not even in its first section; no browned
spot in the leaf at the start of the mine. Sides of the
corridor irregularly scalloped. The corridor mostly begins
close to the leaf margin, often near the tip of the leaf.
The coiled frass is brown or black, even in fresh mines;
the frass fills most of the width of the corridor, but always
leaves a transparent zone at either side. Pupation external;
exit slit in the upper epidermis (Bladmineerders
van Europa).
Leaf-mine:
The larvae feed on the leaves of lime and birch, mining
the leaves when young (UKMoths).
Oviposition
at the leaf upperside. Mine a short, irregular, full depth
corridor, always at the leaf margin, generally in the tip
of the leaf. Frassly broadly scattered. The older larva
lives free on the leaf (Bladmineerders
van Europa).
Leaf-mine:
A
very clear blotch, without preceding corridor, usaally harbouring
several crimson marbled larvae. The mine mostly begins near
the base of the midrib. Most frass is ejected from the mine,
but some of the grains are trapped in a loose spinning below
the leaf, that has been made by the larvae during excursions.
The larvae can leave their mine and restart elsewhere (Bladmineerders
van Europa).
Leaf-mine:
Full depth blotch, invariably beginning at the leaf tip
or the tip of a leaf lobe or tooth. Oviposition site covered
by a black, shining drop of hardened secretion. Frass generally
in long threads, but sometimes in elongated granules (Bladmineerders
van Europa).
Leaf-mine:
Oviposition in the midrib. From there a corridor the larva
enters the lamina which suddenly and strongly widens. The
larva finally pupates in a globular cocoon inside the mine.
Because the mine is formed when the leaf already is fully
developed mined leaves have a normal shape (Bladmineerders
van Europa).
Leaf-mine:
The larvae mine the leaves at first, then create small feeding
windows (UKMoths).
Small,
full depth, hook-like corridor, usually in a vein axil,
with a proportionally large larval chamber. The remainder
of the mine almost entirely stuffed with frass. At the start
if the mine an iridescent egg shell. The larvae soon leave
their mine and start living free on the leaf (Bladmineerders
van Europa).
Leaf-miner
and case-bearer: The early case is tiny and the larva
makes a series of tiny holes on the leaf. After overwintering
it makes a shiny pistol shaped case in spring and window
feeds (British
leafminers).
The
young larva, before hibernation, makes tiny mines, sometimes
tens in one leaf. After hibernation window feeding is done.
In this latter stage the larva lives in a shining black
pistol case of about 7 mm, that, with a mouth angle of 70°-80°,
stands almost perpendicular on the leaf (Bladmineerders
van Europa).
Feeding
damage caused by Coleophora anatipennella
Image: Ian Thirlwell (British
leafminers)
Leaf-miner
and case-bearer:
The larva creates a succession of cases, in this instance
fashioned from parts of a leaf. The final case is 11-13
mm long, slender, and fixed at 45° to the leaf surface,
with anal end laterally compressed and bivalved (British
leafminers).
A
slender, brown, spathulate leaf case, in the end about 13
mm long; mouth angle about 15°. Young case slender,
not hooked (Bladmineerders
van Europa).
Leaf-mine:
The young larva mines the leaves of its foodplant then hibernates.
It will then mines leaves or flowerbuds, then blossom or
leaves (British
leafminers).
Branched,
sometimes stellate, brownish, very transparent, sometimes
long corridor that contains no frass. All frass is ejected
through a number of tiny openings that generally are close
to a vein. Only the young larvae are miners (Bladmineerders
van Europa).
Leaf-mine:
A circular or oval brownish blotch with a central spiral
of dense blackish frass (British
leafminers), sometimes several mines in one leaf (UKMoths).
Oviposition
is at the leaf underside, well away from the leaf margin;
the egg has a fine reticulate surface. The mine is a rather
large, perfectly circular blotch without a trace of a preceding
corridor. Around the dark centre the frass, glued to the
upper epidermis is arranged in distinct arcs (Bladmineerders
van Europa).
