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DACTYLORHIZA. Common-spotted Orchid and Marsh Orchids. [Orchidaceae] |
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Seven species of Dactylorhiza are recorded in Britain. All are native species and include Common-spotted orchid (D. fuchsii), Early Marsh-orchid (D. incarnata), Heath spotted-orchid (D. maculata), Lapland Marsh-orchid (D. traunsteineri lapponica), Narrow-leaved Marsh-orchid (D. traunsteineri traunsteineri), Northern Marsh Orchid (D. pupurella), Southern Marsh-orchid (D. praetermissa) and Western Marsh-orchid (D. majalis). Dactylorhiza majalis is treated as Dactylorhiza kerryensis by Stace (2010). The Lapland Marsh-orchid (D. lapponica) is protected under Schedule 8 of the Wildlife and Countryside Act, 1981. The Narrow-leaved Marsh-orchid (D. traunsteineri) is protected in Northern Ireland under Schedule 8 of the Wildlife (Northern Ireland) Order, 1985. |
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Elsewhere the scatophagid Parallelomma vittatum and the psilid Chyliza vittata are recorded mining Dactylorhiza. No non-Diptera miners are recorded on Dactylorhiza in Britain. Elsewhere one British non-Diptera miner, Orthochaetes insignis, is recorded on Dactylorhiza (see below). A key to the European miners, based on characteristics of the mines, immature stages and where relevant the larval cases, recorded on Orchis and Dactylorhiza is provided in Bladmineerders van Europa. This includes Parallelomma vittatum (as Americina vittata), Chyliza vittata, Delina nigrita, Orthochaetes insignis. |
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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: Large blotch with a group of some larvae. At the start of the mine a group of elliptic egg shells. Pupation outside the mine.
Chyliza vittata Meigen, 1826 [Diptera: Psilidae]. |
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Key for the identification of the mines of British
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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).
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1 > Leaf-miner: Rather narrow corridor, untidy and sometimes branched, starting from the base of the leaf, in particular the midrib. Sides of the corridor irregularly eaten out, not really parallel. Frass mostly present, and then in a central line. The legless larva is capable of leaving the mine and start a new one elsewhere. These later mines are much broader, and the frass is scattered irregularly (Bladmineerders van Europa). Larva without abdominal legs.
Orthochaetes insignis (Aube, 1863) [Coleoptera: Curculionidae] |
| Last updated 04-Feb-2012 Brian Pitkin |  |
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