Key for the identification of the known mines of British
insects (Diptera and non-Diptera) recorded on Apera

1a > Leaf-miner: The young larva first feeds towards the apex of the leaf, later turning and feeding downwards. Several larvae can occur together in a single leaf. Pupation external (Spencer, 1976: 130).

Upper-surface, greenish, gradually widening corridor, at first running towards the leaf tip, then reverses. Through fusion of several mines the final mine is often communal. Frass in backish green grains, often washed out. Pupation outside the mine.

Puparium reddish brown

On Arrhenatherum, Dactylis, Elymus, Hordeum, Phalaris, Secale and Triticum in Britain and additional genera of grasses elsewhere. Widespread in Britain and continental Europe. Also recorded in the East Palaearctic.

Agromyza nigrociliata Hendel, 1931 [Diptera: Agromyzidae].

1b > Leaf-miner: A linear mine running towards the apex of the leaf and this can widen and become almost blotch-like. Pupation internal (Spencer, 1976: 194, 195 (fig. 340).

Upper surface corridor, mostly in the lower half of the blade, running upwards, and never occuping more than half the width of the leaf. Larva solitary. Frass in green smears. Pupation inside the mine.

On Dactylis, Elymus, Phalaris and Triticum, but not yet on Apera, in Britain and additional genera of grasses, including Apera, in continental Europe. Uncommon in England. Widespread in continental Europe. Also recorded in Japan and Canada.

Cerodontha lateralis (Macquart, 1835) [Diptera: Agromyzidae].

1c > Leaf-miner: Normally several larvae feed together. Pupation in the mine (Spencer, 1976: 198).

Broad elongated blotch. Frass greenish. Larvae generally communal. Pupation within the mine. The black puaria are individially anchored within the mine with a silken thread attached at their rear end. Distinguishable from C. incisa only by means of the larva.

On Arrhenatherum, Brachypodium, Bromus, Bromopsis, Calamagrostis, Dactylis, Deschampsia, Elymus, Festuca, Holcus, Lolium, Molinia and Phalaris, but not yet on Apera, in Britain and additional grasses elsewhere. Widespread and common in Britain. Also recorded in the Republic of Ireland. Widespread and frequently common in much of Europe. Also recorded in Alaska and Canada.

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

1d > Leaf-miner: Upper-surface corridor, generally in the upper half of the blade, running up to the leaf tip, usually occupying more then half the width of the leaf. Frass in green stripes at either side of the corridor. Never more than one larva in a mine. Puparium within the mine, metallic black, not anchered with a string of silk.

On Ammophila and Elymus, but not yet on Apera, in Britain and additional grasses including Apera, elsewhere. Known only from Norfolk and Elgin in Britain. Widespread in continental Europe. Also recorded in Canada and the U.S.A.

Cerodontha superciliosa (Zetterstedt, 1860) [Diptera: Agromyzidae].

1e > 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.

Polyphagous. On numerous genera of grasses, but not yet on Apera, 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].

1f > 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.

On Bromus, Dactylis, Holcus and Poa, but not yet on Apera, 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].

1g > Leaf-miner: A short narrow mine, generally near apex of leaf. Larva with each segment bearing a row of characteristic papilli which are retained in the puparium (Spencer, 1976: 328). Pupation internal.

Transparent, short and narrow mine not far from the leaf tip. Frass in two rows of grains. Pupation outside the mine.

On Avena, Dactylis, Holcus, Hordeum, Lolium, Phalaris, Phragmites, Poa and Secale, but not yet on Apera, in Britain and additional other genera of grasses elsewhere. Widespread, but local, in south of Britain. Widespread in continental Europe. Also recorded in Canada.

Pseudonapomyza atra (Meigen, 1830) [Diptera: Agromyzidae].

1h > 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).

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 Apera, 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].