TRITICUM. Wheats. [Poaceae]

Seven species of Triticum are recorded in Britain. All are introduced and include Bread Wheat (T. aestivum) and Rivet Wheat (T. turgidum).

Five Diptera miners, the agromyzids Agromyza mobilis, Agromyza nigrociliata, Agromyza rondensis, Cerodontha lateralis and Chromatomyia nigra, are recorded on Triticum in Britain. Miners on grasses should be reared, whenever possible, to confirm their identity.

Elsewhere the agromyzids Agromyza albipennis, Agromyza ambigua, Agromyza intermittens, Agromyza luteitarsis, Agromyza mobilis, Agromyza nigrella, Agromyza nigrociliata, Agromyza prespana, Agromyza rondensis, Cerodontha denticornis, Cerodontha incisa, Cerodontha lateralis, Cerodontha pygmaea, Cerodontha superciliosa, Chromatomyia fuscula, Chromatomyia nigra and Pseudonapomyza atra and the ephydrid Hydrellia griseola are recorded mining Triticum.

No non-Diptera miners are recorded on Triticum in Britain.

Elsewhere three British non-Diptera leaf-mines are recorded on Triticum (see below).

Key for the identification of the mines of British non-Diptera recorded on
Triticum

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).

Recorded on Dactylis, Deschampsia and Holcus, but not yet on Triticum, in Britain plus Luzula, Agrostis, Alopecurus, Arrhenatherum, Avena, Avenula, Brachypodium, Bromus, Calamagrostis, Elymus, Festuca Koeleria, Phalaris, Phleum, Poa, Trisetum and Triticum elsewhere. Widespread in Britain, Ireland and continental Europe.

 

Elachista albifrontella (Hübner, 1817) [Lepidoptera: Elachistidae].

1b > Leaf-miner: The larvae mine the blades of various grasses, including meadow-grass and cock's-foot (UKMoths). Long, flat, whitish, relatively broad corridor descending from the leaf tip. Frass irregularly scattered. The larva may make several mines during its lifetime. Pupation outside the mine (Bladmineerders van Europa).

Recorded on Dactylis, Holcus and Poa, but not yet on Triticum, in Britain plus Agrostis, Bromus, Festuca, Holcus, Koeleria, Trisetum and Triticum elsewhere. Widespread and reasonably common throughout much of the British Isles except the very far north. Widespread in continental Europe.

 

Elachista freyerella (Hübner, 1825) [Lepidoptera: Elachistidae].

1c > Leaf-miner: Larva makes a large whitish blotch and mines the leaf downwards. The frass tends to be deposited in the upper part of the mine (British leafminers). Oviposition usually not far from the leaf tip. From there descends an irregular blotch mine. Hering (1957a) describes the mine as flat and quite shallow, giving it a greenish, rather than whitish appearance. Frass initially in the oldest, upper part of the mine, later in strings. The larva can leave its mine and restart elsewhere. Normally only one larva per mine, but sometimes two or even three mines in a leaf. Pupation outside the mine (Bladmineerders van Europa).

Recorded on Dactylis, Phalaris, Phragmites and Poa, but not yet on Triticum, in Britain plus Agrostis, Alopecurus, Arrhenatherum, Brachypodium, Calamagrostis, Elymus, Festuca, Holcus, Trisetum and Triticum elsewhere. Widely distributed in Britain, Ireland and continental Europe.