Glyceria [Poaceae]

GLYCERIA. Sweetgrasses. [Poaceae]

Six species of Glyceria are recorded in Britain. Thes include the native Small Sweet-grass (G. declinata), Floating Sweet-grass (G. fluitans), Reed Sweet-grass (G. maxima) and Plicate Sweet-grass (G. notata).

Five Diptera miners, the agromyzids Agromyza albipennis, Agromyza alunulata, Agromyza lucida, Agromyza nigrella and Agromyza nigripes are recorded on Glyceria in Britain. Miners on grasses should be reared, whenever possible, to confirm their identity.

The British chironomid Cricotopus tricinctus is recorded on Glyceria by Cranston in Chandler (1978) and the British ephdrid Hydrellia thoracica is recorded on Glyceria by Irwin and Chandler in Chandler (1978), but it is not clear whether these host associations are British or Foreign. The larvae of a number of species of Chironomidae (non-biting midges) live in tunnels in decaying leaf sheaths under water. Their tunnels are open at both ends, and the larvae feed on particles they obtain from a water current they create in the tunnels. They do not feed on tissues of their 'hostplant' and therefore are not strictly miners (Bladmineerders van Europa).

Elsewhere the agromyzids Agromyza albipennis, Agromyza lucida, Agromyza nigrella, Agromyza nigripes, Cerodontha pygmaea and Chromatomyia nigra and the ephydrids Hydrellia griseola and Hydrellia thoracica are recorded mining Glyceria.

Two non-Diptera miners are recorded on Glyceria in Britain (see below).

Elsewhere four additional British non-Diptera miners are recorded on Glyceria (see below).

The larvae of a number of species of Chironomidae (see Cricotopus brevipalpis, Criciotopus tricinctus and Cricotopus trifasciatus) live in tunnels in decaying leaf sheaths under water. Their tunnels are open at both ends, and the larvae feed on particles they obtain from a water current they create in the tunnels. They do not feed on tissues of their 'hostplant' and therefore are not strictly miners (Bladmineerders van Europa).

A key to the European miners, based on characteristics of the mines, immature stages and where relevant the larval cases, recorded on Glyceria is provided in Bladmineerders van Europa. This includes Agromyza albipennis, Agromyza alunulata, Agromyza nigrella, Agromyza nigripes, Agromyza lucida, Chromatomyia nigra, Cerodontha pygmaea, Hydrellia griseola, Hydrellia thoracica, Donacaula forficella, Elachista poae, Elachista pomerana, Orthotelia sparganella and Sedina buettneri.

Key for the identification of the mines of British Diptera recorded on
Glyceria

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: Larvae feed singly, forming an upper surface linear-blotch mine. Pupation either internal or external. Puparium reddish, brown or black, loosely glued to the leaf.

Mine of Agromyza albipennis on Phalaris arundinacea. Image: Willem Ellis (Source: Bladmineerders van Europa)

Mine of Agromyza albipennis on Phalaris arundinacea
Image: Willem Ellis (Bladmineerders van Europa)

On Arrhenatherum, Brachypodium, Bromus, Dactylis, Glyceria, Holcus, Hordeum, Milium, Phalaris and Poa in Britain and additional grasses elsewhere. Widespread and common in Britain. Also recorded in the Republic of Ireland. Very common in western Europe and recorded in Canada.

Agromyza albipennis Meigen, 1830 [Diptera: Agromyzidae].

1b > Leaf-miner: A blotch mine, larvae feeding first towards apex of leaf and then downwards towards base. Pupation external. Puparium dimorphic, summer form of normal shape, red and thin shelled; winter form black, thick shelled and strongly arched.

On Glyceria in Britain and elsewhere. Uncommon in Britain. Surrey and Warwick. Local in western Europe.

Agromyza alunulata (Hendel, 1931) [Diptera: Agromyzidae].

1c > Leaf-miner: Larvae either singly or several in leaf, then forming large blotch, feeding first up and then down the leaf. Pupation external; puparium adhering to the leaf near end of mine, puparium black or dark red

On Dactylis, Deschampsia and Glyceria in Britain and Deschampsia, Echinaria and Glyceria elsewhere. Widespread in Britain and continental Europe. Also recorded in Canada.

Agromyza lucida Hendel, 1920 [Diptera: Agromyzidae].

1d > Leaf-miner: Larval leaf mine starts as a narrow channel running towards apex of leaf but later develops into a broad blotch running downwards. Frass largely diffused, giving the mine a characteristic greenish appearance. Pupation external. Puparium reddish brown

On Dactylis, Festuca, Glyceria, Holcus, Lolium, Phleum, Poa, Secale, Setaria and Trisetum in Britain and additionally other genera of grasses elsewhere. Widespread in Britain. Common and widespread thoughout much of Europe. Also recorded in the U.S.A.

Agromyza nigrella (Rondani, 1875) [Diptera: Agromyzidae].

1e > Leaf-miner: Larvae feeding singly, forming a long, widening mine on the upper surface of the leaf, which is generally limited to one side of the leaf. Pupation external. Puparium varying from black to reddish, glued to the leaf near the end of the mine

On Glyceria and Holcus in Britain and additional genera of grasses in continental Europe. Widespread and common in Britain. Widespread in continental Europe. Also recorded in Canada.

Agromyza nigripes Meigen, 1830 [Diptera: Agromyzidae].

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

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).

1a > Leaf miner / Stem-borer: Narrow gallery in a young leaf. After having mined for some time the larva becomes a borer in the stem or rhizome ( Bladmineerders van Europa). The larvae feed inside the stems (UKMoths).

Recorded on Scirpus, Glyceria, Iris, Sparganium and Typha, but not yet on Glyceria, in Britain and Schoenoplectus, Glyceria, Iris and Sparganium elsewhere. Locally distributed from southern England northwards to southern Scotland. Also recorded in the Republic of Ireland. Widespread in continental Europe.

Orthotelia sparganella (Thunberg, 1788) [Lepidoptera: Glyphipterigidae].

1b > Leaf-miner: Common reed and similar plants are the larval foodplant. The larva of this species has a peculiar habit of cutting part of a leaf to act as a raft, using this to float on the water to a new foodplant when necessary (UKMoths). Narrow, whitish, rather inflated corridor, sometimes several tens of centimeters long, running towards the leaf sheath. Frass in coarse grains, in a distinct central line. Now and then the larva makes a elongate case from leaf material and uses it to float to another hostplant. The case may stick for some time to the new host. The larva pupates in a stem, after having made an exit hole and closed it with silk (Bladmineerders van Europa).

Recorded on Phragmites australis, but not yet on Glyceria, in Britain and Carex, Glyceria and Phragmites elsewhere. Southern half of Britain. Also recorded in the Republic of Ireland. Widespread in continental Europe.

Donacaula forficella (Thunberg, 1794) [ Lepidoptera: Crambidae].

1c > Leaf-miner: Corridor widening while descending from the tip of the leaf. The mine is unusual because the sides are very irregularly scalloped out. Moreover, the mine is not evenly transparent, but rather yellowish green and motly, because the larva leaves patches of parenchyma uneaten, and does not feed full depth. Frass in a few irregular, interrupted length lines. Often 2-3 larvae in a mine. The larvae hibernate in the centre of the mine; after winter they leave their mine and pupate ( Bladmineerders van Europa).

Recorded on 'various grasses', but not yet on Glyceria, in Britain plus Luzula, Agrostis, Arrhenatherum, Brahcypodium, Calamagorstis, Dactylis, Deschampsia, Elymus, Festuca, Glyceria, Holcus, Melica, Milium and Poa elsewhere. Widespread in Britain, Ireland and continental Europe.

Elachista apicipunctella Stainton, 1849 [Lepidoptera: Elachistidae].

1d > Leaf-miner: Narrow, whitish (in the end often reddish brown) gallery of several decimeters in length, descending from the leaf tip to within the sheath of the leaf. Frass dispersed. Pupation external (Bladmineerders van Europa).

Recorded on Poa, but not yet on Glyceria, in Britain and elsewhere. Southern England and Wales. Also recorded in the Republic of Ireland. Widespread in continental Europe.

Elachista poae Stainton, 1855 [Lepidoptera: Elachistidae].

1e > Leaf-miner: The mine begins near the leaf tip and descends towards the base. The mine occupies the entire width of the blade. Frass initially scattered, later in an irregular central line. Fully developed mine c. 8 cm long. Probably the larva is capable of leaving its mine and restarting in another leaf. Pupation external (Bladmineerders van Europa).

Recorded on Calamagrostis epigejos, but not yet on Glyceria, in Britain and Avena, Calamagrostis, Glyceria, Phalaris and Poa elsewhere. Cambridge and East Norfolk in Britain. Widespread in continental Europe.

Elachista pomerana Frey, 1870 [Lepidoptera: Elachistidae].

1f > Leaf-miner: When young, the larva mines mainly the leaves or the stem of Sparganium or Nuphar lutea. It hibernates. Later it lives amongst spun leaves just below the surface of the water. Pupation in a white silk cocoon attached to the foodplant at or just below the water-level (Belgian Lepidoptera). Long narrow corridor, on or alongside the midrib. The corridor may descend below the water surface, and does contain frass. After some time the larva cuts itself a case out of the mine, and continues living free, partly under water (Bladmineerders van Europa).

Recorded on Nuphar and Sparganium, but not yet on Glyceria, in Britain and Glyceria, Nuphar, Nymphaea, Potamogeton and Sparganium elsewhere. Widespread in Britain. Also recorded in the Republic of Ireland. Widespread in continental Europe.

Nymphula nitidulata (Hufnagel, 1767) [Lepidoptera: Crambidae].


	Last updated 05-Feb-2012 Brian Pitkin