|
APIUM. Wild Celery, Fool's-water-cress and Marshworts. [Apiaceae] |
|
Four species of Apium are recorded in Britain - Wild Celery (A. graveolens), Fool's-water-cress (A. nodiflorum), Lesser Marshwort (A. inundatum) and Creeping Marshwort (A. repens). All are native species. Creeping Marshwort (A. repens) is protected under Schedule 8 of the Wildlife and Countryside Act, 1981. Only one Diptera miner, the tephritid Euleia heraclei, is recorded on Apium in Britain. The polyphagous agromyzids Liriomyza bryoniae and Liriomyza strigata are recorded on Apium, but their occurences on this host in Britain require confirmation. The polyphagous agromyzids Liromyza huidobrensis and Liriomyza trifolii have been recorded in quarantine in Britain (Pitkin and Plant in British leafminers). Elsewhere the agromyzids Chromatomyia horticola, Napomyza carotae, Liriomyza bryoniae, Liriomyza huidobrensis, Liriomyza sativae and Liriomyza trifolii, and the tephritid Euleia heraclei are recorded mining Apium. No non-Diptera miners are recorded on Apium in Britain. Elsewhere one British non-Diptera miner, Epermenia chaerophyllella, is recorded on Apium (see below). A key to the European miners, based on characteristics of the mines, immature stages and where relevant the larval cases, recorded on Apium is provided in Bladmineerders van Europa. This includes Epermenia chaerophyllella, Euleia heraclei, Euleia separata, Chromatomyia horticola, Liriomyza strigata and Liriomyza bryoniae but not Napomyza carotae, Liriomyza huidobrensis, Liriomyza sativae or Liriomyza trifolii. N.B. The key to mines below includes mines recorded on Apium and Levisticum (Apiaceae) and Lavatera (Malvaceae). |
|
|
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). 1 > 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.
Euleia heraclei (Linnaeus, 1758) [Diptera: Tephritidae]. |
|
Key for the identification of the mines of British non-Diptera recorded on
|
|
|
Note: The larvae of mining Coleoptera, Hymenoptera and Lepidoptera 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. Larva may pupate in a silk cocoon. The larva may have at least six 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). 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. Pupa with visible head appendages, wings and legs which lie in sheaths (see examples).
|
|
|
1 > Leaf-miner: The larvae are often gregarious and feed on the underside of the leaf causing a 'windowing' effect as they eat the mesophyll and lower epidermis. This effect can be seen from the top of the leaf as it discolours (British leafminers). Short, small, irregular, sometimes widened corridor. Mostly a number in a leaf, concentrated in the axils of the midrib and the primary side veins. Each larva makes a number of mines. Often the larva protrudes with its rear end out of the mine, causing most frass to be ejected. While moving, at the leaf underside, silken threads are produced, in wich grains of frass may be trapped. Older larvae live free and cause window feeding, often in a group under a light spinning (Bladmineerders van Europa).
Epermenia chaerophyllella (Goeze, 1783) [Lepidoptera: Epermeniidae] |
| Last updated 03-Feb-2012 Brian Pitkin |  |
|