The leaf and stem mines of British flies and other insects
 

(Coleoptera, Diptera, Hymenoptera and Lepidoptera)

by Brian Pitkin, Willem Ellis, Colin Plant and Rob Edmunds

N.B. Links to the latest version of 'Leafminers and plant galls of Europe' are being edited

Join us on Facebook

ALOPECURUS. Foxtails. [Poaceae]


Six species and three hybrids of Alopecurus are recorded in Britain. These include the native species Orange Foxtail (A. aequalis), Black-grass (A. myosuroides), Alpine Foxtail (A. borealis), Bulbous Foxtail (A. bulbosus), Marsh Foxtail (A. geniculatus) and Meadow Foxtail (A. pratensis). The BSBI provide a downloadable plant crib for Alopecurus.

Thirteen British miners are recorded on Alopecurus.

A key to the European miners recorded on Alopecurus is provided in Bladmineerders van Europa.

Nearly 100 British miners or possible miners are recorded on grasses in Britain.

It is recommended that adults of all miners on grasses be reared to be certain of their identity.



Key for the identification of the known mines of British
Diptera recorded on Alopecurus


Note: Diptera larvae may live in a corridor mine, a corridor-blotch mine, or a blotch mine, but never in a case, a rolled or folded leaf, a tentiform mine or sandwiched between two more or less circular leaf sections in later instars. Pupation never in a cocoon. All mining Diptera larvae are leg-less maggots without a head capsule (see examples). They never have thoracic or abdominal legs. They do not have chewing mouthparts, although they do have a characteristic cephalo-pharyngeal skeleton (see examples), usually visible internally through the body wall. The larvae lie on their sides within the mine and use their pick-like mouthparts to feed on plant tissue. In some corridor miners frass may lie in two rows on alternate sides of the mine. In order to vacate the mine the fully grown larva cuts an exit slit, which is usually semi-circular (see Liriomyza huidobrensis video). The pupa is formed within the hardened last larval skin or puparium and as a result sheaths enclosing head appendages, wings and legs are not visible externally (see examples).

See Key to non-Diptera.


1a > Leaf-miner: Larva feeds mainly in the leaf sheaths. The short mines which may be formed in the leaf blade may be easily overlooked. Pupation internal (Spencer, 1976: 178).

Mine begins as a narrow, usually upper-surface, occasionally lower-surface or interparenchymatous corridor in the blade, that descends towards the ligule, thence continues into the leaf sheath, generally on its inside. Usually only one mine per leaf. Puparium in a pupariuml chamber at the margin of the leaf sheath. Neither mine nor larva can be distinguished from that of C. fulvipes that, as far as is known, only feeds on Poa trivialis (Bladmineerders van Europa).

On Alopecurus, Elymus, Festuca, Holcus and Phalaris, but not yet on Alopecurus, in Britain (including the Channel Is.) and additional grasses elsewhere. Widespread from the southern England to Scotland, most northerly record Outer Hebrides. Also recorded in the Republic of Ireland, Europe, Africa and Japan.

Cerodontha denticornis (Panzer, 1806) [Diptera: Agromyzidae].

1b > Leaf-miner: Lower-surface corridor; larva solitary. Pupation mostly outside the mine (Bladmineerders van Europa).

On Calamagrostis in Britain and elsewhere. Also on Alopecurus elsewhere. Widespread in continental Europe.

Cerodontha calamagrostidis Nowakowski, 1967 [Diptera: Agromyzidae].

1c > Leaf-miner: A lower surface mine. Pupation normally in the ground (Spencer, 1976: 202).

Broad, usually lower-surface corridor in the blade, generally first rising, then descending. Mostly one larva in a mine, but sometimes several mines on a leaf may merge. Frass in grains that gradually become both larger and more widely spaced. Pupation outside the mine (Bladmineerders van Europa).

On Agrostis, Arrhenatherum, Dactylis, Elymus, Festuca, Holcus and Poa, but not yet on Alopecurus, in Britain. On Elytrigia elsewhere. Widespread in Britain and continental Europe. Also Canada.

Cerodontha flavocingulata (Strobl, 1909) [Diptera: Agromyzidae].

1d > Leaf-miner: Broad elongated mine; the form is dependent of the leaf form of the host plant. Frass green. Usually a number of larvae together in a mine. Pupation in the mine (Bladmineerders van Europa).

On Bromopsis, Dactylis, Elymus and Phalaris, but not yet on Alopecurus, in Britain and additional grasses, including Elytrigia, elsewhere. Widespread in Britain. Also recorded in the Republic of Ireland. Widespread and common in continental Europe. Also recorded in Japan, U.S.A. and Canada.

Cerodontha incisa (Meigen, 1830) [Diptera: Agromyzidae].

1e > Leaf-miner: Long upper-surface corridor usually containing several larvae that graze shoulder to shoulder from the leaf tip downwards. Pupation outside the mine. Mines and larvae are indistinguishable from those of A. nigrella (Bladmineerders van Europa).

On Bromus, Bromopsis, Elymus, Holcus, Phleum and Triticum, but not yet on Alopecurus, in Britain and additional grasses elsewhere. Widespread in Britain and continental Europe.

Agromyza mobilis Meigen, 1830 [Diptera: Agromyzidae].

1f > Leaf-miner: Larval leaf-mine starts as a narrow channel running towards apex of leaf but later develops into a broad blotch running downwards. Frass largely diffused, giving the mine a characteristic greenish appearance. Pupation external (Spencer, 1976: 126).

Corridor, usually several in one leaf, running from close to the leaf base up to near the tip, then reversing direction and widening, resulting in one communal mine in which the larvae descend in a common front . Frass somewhat deliquescent, mine therefore strikingly green. Pupation outside the mine. Neither mine nor larva distinguishable from those of mobilis (Bladmineerders van Europa).

Puparium reddish brown

On Dactylis, Festuca, Glyceria, Holcus, Lolium, Phleum, Poa, Secale, Setaria, Trisetum and Triticum, but not yet on Alopecurus, in Britain and additionally other genera of grasses elsewhere. Widespread in Britain. Common and widespread thoughout much of Europe. Also recorded in the U.S.A.

Agromyza nigrella (Rondani, 1875) [Diptera: Agromyzidae].

1g > Leaf-miner: Larvae feeding singly, forming a long, widening mine on the upper surface of the leaf, which is generally limited to one side of the leaf. Pupation external, puparium glued to the leaf near the end of the mine (Spencer, 1976: 128).

Broad corridor, generally beginning near the leaf margin or close to the leaf tip. Most of the times the mine remains at one side of the midrib. The mine is upper-surface, but has some full depth, translucent spots here and there. Frass in rather regularly scattered grains. Pupation outside the mine. According to Dempewolf (2004a) only the male genitalia enable a reliable discrimination from A. abipennis and A. graminicola (Bladmineerders van Europa).

On Glyceria and Holcus, but not yet on Alopecurus, in Britain and additional genera of grasses, including Elytrigia, in continental Europe. Widespread and common in Britain. Widespread in continental Europe. Also recorded in Canada.

Agromyza nigripes Meigen, 1830 [Diptera: Agromyzidae].

1h > Leaf-miner: Narrow whitish mine, with frass in distinct black lumps. Pupation internal (Spencer, 1976: 422).

Whitish, upper-surface, descending corridor, about halfway up the blade. Frass in distinct black grains that are lying further apart than their diameter. Pupation in the mine (Bladmineerders van Europa).

On Arrhenatherum, Holcus, Milium and Phleum, but not yet on Alopecurus, in Britain and additional grasses elsewhere. Recorded in Scotland and Widespread in continental Europe. Also recorded in Canada.

Chromatomyia fuscula (Zetterstedt, 1838) [Diptera: Agromyzidae].

1i > Leaf-miner: Long, narrow, whitish mine. Pupation internal (Spencer, 1976: 453); anterior spiracles projecting through the epidermis.

Whitish, upper-surface, rather narrow corridor with comparatively large frass grains that are laying further apart than their diameter. Pupation within the mine. The anterior spiracles of the orange-brown puparium penetrate the epidermis (Bladmineerders van Europa).

Chromatomyia nigra larva,  lateral
Chromatomyia nigra larva, lateral
Image: © Willem Ellis (Bladmineerders van Europa)
Orchestes fagi larva,  dorsal
Chromatomyia nigra pupa, lateral
Image: © Willem Ellis (Bladmineerders van Europa)

Polyphagous. On numerous genera of grasses, but not yet on Alopecurus, in Britain. Widespread and common throughout British Isles and much of Europe. Also recorded in Canada, western U.S.A. and Japan.

Chromatomyia nigra (Meigen, 1830) [Diptera: Agromyzidae].

1j > Leaf-miner: A narrow whitish linear mine, running down the leaf from the apex, with frass in two rows of separate grains. Pupation external (Spencer, 1976: 246).

Narrow corridor from start to end, whitish, uppper- or lower-surface, genarally running downwards. Mine often along the leaf margin. Frass in distict grains of regular size, alternating along the sides of the corridor. Pupation outside the mine (Bladmineerders van Europa).

Mine of Liriomyza flaveola on Festuca gigantea. Image: © Willis Ellis (Source: Bladmineerders en plantengallen van Europa)
Mine of Liriomyza flaveola on Festuca gigantea
Image: © Willis Ellis (Bladmineerders van Europa

On Bromus, Dactylis, Holcus and Poa, but not yet on Alopecurus, in Britain and additional grasses elsewhere. Common and widespread throughout Britain. Also recorded in the Republic of Ireland. Common throughout much of Europe.

Liriomyza flaveola (Fallén, 1823) [Diptera: Agromyzidae].

1k > Leaf-miner: Upper surface, deep, narrow mine; frass in two regular rows; pupation external (Spencer, 1972b: 60, as flavoscutellaris).

A short, descending corridor in a leaf sheath. Fress in few, isolated blad granules. Pupation outside the mine (Bladmineerders van Europa).

On Carex, but not yet on Alopecurus, in Britain and Alopecurus, Deschampsia and Holcus elsewhere. Widespread in south in Britain. Also recorded in the Republic of Ireland. Widespread in continental Europe.

Metopomyza flavonotata (Haliday, 1833) [Diptera: Agromyzidae].

 


Key for the identification of the known mines of British
non-Diptera recorded on Alopecurus


Note: Larvae of mining Coleoptera, Hymenoptera and Lepidoptera usually have six thoracic legs (although they may be reduced or absent), a head capsule and chewing mouthparts with opposable mandibles (see video of a gracillarid larva feeding). Larvae of Hymenoptera and Lepidoptera usually also have abdominal legs (see examples). Larva may live in a corridor mine, a corridor-blotch mine, a blotch mine, a case, a rolled or folded leaf, a tentiform mine or sandwiched between two more or less circular leaf sections in later instars. Frass, if present, never in two rows. Unless feeding externally from within a case the larva usually vacates the mine by chewing an exit hole.

The mines of Elachista are insufficiently known to identify and adults should be reared.

1a > Leaf/Stem miner: The larvae mine the stems of various coarse grasses (UKMoths; Plant in Pitkin & Plant, 2005).

The larva mines just a few days in the leaf, then continues as a stem borer on the lower part of the stem. They regularly move to a new stem. The central leaves of the infested plants wither and die (Bladmineerders van Europa).

On Dactylis and Poa, but not yet on Alopecurus, in Britain and Alopecurus, Avena, Bromus; Dactylis, Hordeum, Poa, Secale and Triticum elsewhere. Widespread in England and Wales. Also recorded in the Republic of Ireland. Widespread in continental Europe.

Ochsenheimeria taurella (Denis & Schiffermüller, 1775) [Lepidoptera: Ypsolophidae].

1b> Seed-feeder, leaf-miner and case-bearer: Initially it feeds on the seeds of thyme and then uses the seedhead as a case. It overwinters in this case and starts feeding again in March on grass spp. It then makes a case from the mined blade of grass (British leafminers). The larva initially feeds on the seeds of thyme, feeding within a floret and using this as its case. After overwintering, it changes foodplants to grass, and eventually forms an elongated case from two grass blade portions sewn together (UKMoths). The larva begins its life by eating out the ripe fruit of a thyme floret. The emptied and dried calyx functions as its first case, in which it hibernates. After hibernation the larva switches to grasses, initially in its original thyme case. Later a new case is made out of a mined grass leaf. This final case is about 11 mm long, two-valved, straw-coloured, has a mouth angle of 25°, and bears a striking resemblance to a grass spikelet (Bladmineerders van Europa).

On Thymus and the grasses Anthoxanthum odoratum, Briza media, Dactylis glomerata, Holcus lanata and Poa annua, but not yet on Alopecurus, in Britain and these grasses plus Alopecurus pratensis, Avenula pubescens, Bromus hordaceus, Elymus and Koeleria elsewhere. Widespread in Britain and continental Europe. Also recorded in the Republic of Ireland.

Coleophora lixella Zeller, 1849 [Lepidoptera: Coleophoridae]

1c > Leaf-miner: The larva mines from the grass tip downwards and the mine occupies half or the whole of the leaf blade width. A whitish blotch is formed with characteristic narrow streaks of frass (British leafminers). Full depth blotch, slightly inflated, descending from the leaf tip, occupying half or the entire width of the blade. The larva may move and make a new mine elsewhere. In the latter case the mines are fairly short; otherwise an entire blade may be mined out. Frass in a some narrow greyish brown streaks. Pupation outside the mine (Bladmineerders van Europa).

On Dactylis, Deschampsia and Holcus, but not yet on Alopecurus, in Britain plus Luzula, Agrostis, Alopecurus, Arrhenatherum, Avena, Avenula, Brachypodium, Bromus, Calamagrostis, Elymus, Festuca Koeleria, Phalaris, Phleum, Poa, Trisetum and Triticum elsewhere. Widespread in Britain, Ireland and continental Europe.

Elachista albifrontella (Hübner, 1817) [Lepidoptera: Elachistidae]

1d > Leaf-miner: Larva makes a large whitish blotch and mines the leaf downwards. The frass tends to be deposited in the upper part of the mine (British leafminers). Oviposition usually not far from the leaf tip. From there descends an irregular blotch mine. Hering (1957a) describes the mine as flat and quite shallow, giving it a greenish, rather than whitish appearance. Frass initially in the oldest, upper part of the mine, later in strings. The larva can leave its mine and restart elsewhere. Normally only one larva per mine, but sometimes two or even three mines in a leaf. Pupation outside the mine (Bladmineerders van Europa).

On Dactylis, Phalaris, Phragmites and Poa, but not yet on Alopecurus, in Britain plus Agrostis, Alopecurus, Arrhenatherum, Brachypodium, Calamagrostis, Elymus, Festuca, Holcus, Trisetum and Triticum elsewhere. Widely distributed in Britain, Ireland and continental Europe.

Elachista maculicerusella (Bruand, 1859) [Lepidoptera: Elachistidae]

1d > Leaf-miner: Mine linear, whitish, both upper and lower surface. Pupation internal, at the end of the mine with the anterior spiracles projecting through the epidermis (Spencer, 1976: 433).

Upper-surface, less often lower-surface corridor. Frass in isolated grains. Pupation within the mine, usually in a lower-surface puparial chamber (Bladmineerders van Europa).

A long whitish upper surface corridor, which eventually goes lower surface (British leafminers).

Two highly polyphagous species of Chromatomyia, with indistinguishable mines, have been recorded in Britain. These are syngenesiae (Hardy) and horticola (Goureau) which can only be distinguished by the male genitalia. Both species are widespread in Britain and elsewhere, although syngenesiae is almost entirely restricted to Asteraceae. Records on Asteraceae not based on examination of male genitalia are treated in this account as Chromatomyia 'atricornis'.

Chromatomyia horticola is recorded on 160 plant genera in 31 families, of which 55 plant genera in 19 families, including Tropaeolum, in Britain.

Chromatomyia horticola (Goureau, 1851) [Diptera: Agromyzidae].

1e > Leaf-miner: Irregular mine, locally shallow, elsewhere much deeper, giving it a mottled appearance. In broadleaved plants the mine often begins as a blotch with stellate extensions, but sometimes as a very fine, shallow corridor. In grasses the mine often begins in the leaf sheath. The frass is very fine-grained, initially scattered, later in aggregates. The egg is deposited on the plant surface, and the empty egg shell remains visible. But the larvae are able to leave their mine and restart elsewhere, thus mines without an egg shell can be found as well. The larva also leaves the mine before pupation. Pupation takes place in a newly made, small, blotch mine without frass; this mine may be made in another plant (species) (Bladmineerders van Europa).

Mine of Hydrellia griseola on Glyceria fluitans. Image: © Willem Ellis (Source: Bladmineerders en plantengallen van Europa)
Mine of Hydrellia griseola on Glyceria fluitans
Image: © Willem Ellis (Bladmineerders van Europa)

Polyphagpus. On ? Alisma, ? Damasonium, ? Sagittaria, ? Bellis, ? Rorippa, Tropaeolum, ? Lychnis, ? Stellaria, ? Carex, ? Cyperus, ? Scirpus, ? Hydrocharis, ? Stratiotes, ? Lamium, ? Lemna, ? Allium, Arrhenatherum, ? Polygonum, ? Potamogeton, ? Veronica, ? Typha, but not yet on Alopecurus, in Britain.

On ? Alisma, ? Damasonium, ? Sagittaria, ? Bellis, ? Rorippa, Tropaeolum, Lychnis, ? Stellaria, Carex, ? Scirpus, Trifolium, ? Hydrocharis, Lamium, ? Lemna, Allium, Papaver, Agrostis, Alopecurus, Apera, Arrhenatherum, Avena, Avenula, Brachypodium, Briza, Bromus, Calamagrostis, Dactylis, Desmazeria, Digitaria, Echinochloa, Eleusine, Elymus, Festuca, Gaudinia, Glyceria, Holcus, Hordeum, Lagurus, Lolium, Panicum, Phalaris, Phleum, Phragmites, Poa, Secale, Setaria, Triticum, ? Polygonum, ? Potamogeton, Veronica, ? Typha and Verbena elsewhere. Widespread in England. Also recorded in the Republic of Ireland. Widespread in the Palaearctic region. Also recorded from Nearctic and Australasian Regions.

Hydrellia griseola (Fallén, 1813) [Diptera: Ephydridae].



XHTML Validator Last updated 20-Jun-2017  Brian Pitkin Top of page