|
HIEROCHLOE. Holy-grass. [Poaceae] |
|
Holy-grass (H. odorata) is the only species of Hierochloe recorded in Britain. It is protected in Northern Ireland under Schedule 8 of the Wildlife (Northern Ireland) Order, 1985. Two Diptera miners, the agromyzids Cerodontha muscina and Chromatomyia milii, are recorded on Hierochloe in Britain. Miners on grasses should be reared, whenever possible, to confirm their identity. Elsewhere the agromyzids Chromatomyia milii, Chromatomyia nigra and Cerodontha muscina are recorded mining Hierochloe. One non-Diptera leaf-miner is recorded on Hierochloe in Britain and elsewhere (see below). A key to the european mines recorded on Hierochloe is provided in Bladmineerders van Europa. This includes Cerodontha muscina, Chromatomyia milii and Chromatomyia nigra but not Cerodontha incisa, Cosmopterix orichalcea. |
|
|
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: Broad lower surface mine which generally starts at the leaf apex.The mine is somewhat irregular in depth. Frass in irregular black-green, frequently melted grains, most along the edges of the mine. Larva solitary. Pupation generally internal. Puparium shining metallic bluish-black, posterior spiracles projecting through the epidermis
Cerodontha (Poemyza) muscina (Meigen, 1830) [Diptera: Agromyzidae]. 1b > Leaf miner: A substantial linear mine. Pupation internal. Puparium posterior spiracles projecting through the epidermis.
Chromatomyia milii (Kaltenbach, 1864) [Diptera: Agromyzidae]. |
|
Key for the identification of the mines of British
|
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: Makes long narrow galleries. The frass is distributed through the mine and also some is ejected. The larvae may mine more than one leaf (British leafminers). Elongate, rather irregular blotch. Most frass is ejected, what remains is concentrated in a few heaps. The larva makes several mines. Pupaton outside the mine (Bladmineerders van Europa).
Cosmopterix orichalcea Stainton, 1861 [Lepidoptera: Cosmopterigidae] |
| Last updated 05-Feb-2012 Brian Pitkin |  |
|