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).

1a > Leaf-miner: Blotch mine

2

1b > Leaf-miner: Linear mine.

3

2a > Leaf-miner: A large blotch, yellow or brown, preceded by a short, in the end mostly unrecognisable corridor. Generally several larvae in the mine. Especially in fresh mines the green primary and feeding lines area well marked. Pupation outside the mine.

On Angelica and possibly Arctium and Heracleum in Britain. Widespread but very rare in Britain. Also recorded in the Republic of Ireland and throughout Europe, except in the south.

Cryptaciura rotundiventris (Fallén, 1814) [Diptera: Tephritidae].

2b > Leaf-miner: A large blotch, yellow or brown, preceded by a short corridor that in the end mostly is completely overrun. Generally several larvae share a mine. Especially in fresh mines the green primary and secondary feeding lines are well visible. Pupation outside the mine. Puparium yellow.

On numerous genera of Apiaceae and possibly some Asteraceae in Britain and elsewhere. Throughout the British Isles, including Ammi in Britain. Also recorded in the Republic of Ireland and most of the Palaearctic region, as far east as Afghanistan.

Euleia heraclei (Linnaeus, 1758) [Diptera: Tephritidae].

2c > Leaf-miner: Larva forms an upper surface primary blotch with several larvae feeding together; the blotch is greenish when fresh but becomes yellowish with age (Spencer, 1972: 78 (fig. 257); Spencer, 1976: 376, 377 (fig. 655)). Round or oval blotch, green at first, later yellowish. Young mine are interparenchymatous, only the older mines are truly full depth. Generally several larvae in a communal mine. Pupation outside the mine. Exit slit in lower epidermis (Bladmineerders van Europa). A conspicuous, yellowish, almost circular upper surface blotch. Normally several mines on a leaf which may run together giving the impression of a single mine (British leafminers).

On Aegopodium and Angelica in Britain and elsewhere and Laserpitium elsewhere. Widespread throughout Britain and continental Europe. Also recorded in U.S.A. and Canada.

Phytomyza angelicae Kaltenbach, 1872 [Diptera: Agromyzidae].

3a > Leaf-miner: An irregular upper surface linear mine, which can widen and become almost blotch like at end. Puparium black

On Aegopodium, Angelica and Pastinaca in Britain and Aegopodium and Angelica elsewhere. Widespread throughout Britain. Also recorded in Ireland and Europe.

Phytomyza angelicastri Hering, 1923 [Diptera: Agromyzidae].

3b > Leaf-miner: An irregular whitish linear mine, not associated with leaf margin. Puparium black. British record needs confirmation.

Possibly on Angelica in Britain (Warwicks). On Angelica in continental Europe. Also recorded in Alaska.

Phytomyza archangelicae (Hering, 1937) [Diptera: Agromyzidae].