Key for the identification of the known mines of British
insects (Diptera and non-Diptera) recorded on Alisma

1# > ? Leaf-miner: Details of mine unknown.

On Alisma and Rorippa nasturtium-aquaticum in Britain and elsewhere (record provenances ambiguous). Recorded in South Hants in Britain. Widespread in continental Europe.

Hydrellia meigeni Zatwarnicki, 1988 [Ephydridae].

1a > Leaf-miner: A number of short, rather broad corridors that enter the blade from the midrib. Pupation within the mine, mainly in the leaf base and the midrib. At the moment only adult flies can be separated from H. stratiotae..

On ? Alisma, ? Hydrocharis and ? Stratiotes in Britain and continental Europe.

Hydrellia mutata (Zetterstedt, 1846) [Diptera: Ephydridae].

1b > Leaf-miner: Irregular mine, locally shallow, elsewhere much deeper, giving it a mottled appearance. In broadleaved plants the mine often begins as a blotch with stellate extensions, but sometimes as a very fine, shallow corridor. In grasses the mine often begins in the leaf sheath. The frass is very fine-grained, initially scattered, later in aggregates. The egg is deposited on the plant surface, and the empty egg shell remains visible. But the larvae are able to leave their mine and restart elsewhere, thus mines without an egg shell can be found as well. The larva also leaves the mine before pupation. Pupation takes place in a newly made, small, blotch mine without frass; this mine may be made in another plant (species).

Polyphagpus. On ? Alisma, ? Damasonium, ? Sagittaria, ? Bellis, ? Rorippa, Tropaeolum, ? Lychnis, ? Stellaria, ? Carex, ? Cyperus, ? Scirpus, ? Hydrocharis, ? Stratiotes, ? Lamium, ? Lemna, ? Allium, Arrhenatherum, ? Polygonum, ? Potamogeton, ? Veronica, ? Typha in Britain.

On ? Alisma, ? Damasonium, ? Sagittaria, ? Bellis, ? Rorippa, Tropaeolum, Lychnis, ? Stellaria, Carex, ? Scirpus, Trifolium, ? Hydrocharis, Lamium, ? Lemna, Allium, Papaver, Agrostis, Alopecurus, Apera, Arrhenatherum, Avena, Avenula, Brachypodium, Briza, Bromus, Calamagrostis, Dactylis, Desmazeria, Digitaria, Echinochloa, Eleusine, Elymus, Festuca, Gaudinia, Glyceria, Holcus, Hordeum, Lagurus, Lolium, Panicum, Phalaris, Phleum, Phragmites, Poa, Secale, Setaria, Triticum, ? Polygonum, ? Potamogeton, Veronica, ? Typha and Verbena elsewhere. Widespread in England. Also recorded in the Republic of Ireland. Widespread in the Palaearctic region. Also recorded from Nearctic and Australasian Regions.

Hydrellia griseola (Fallén, 1813) [Diptera: Ephydridae].

1c > Leaf-miner:Shallow upper-surface mine that enters the blade from the petiole. Pupation internal, often in midrib or petiole.

Only on Alisma in Britain and elsehwere. Recorded in England and Wales in Britain. Widespread in continental Europe

Hydrellia flavicornis (Fallén, 1823) [Diptera: Ephydridae].

1d > Leaf-miner: A short, irregular, linear upper surface mine on any part of the leaf. Also recorded from young pods (Bland, 1997a).

Long corridor mine. As a rule the first part of the mine is lower-surface, the later part upper-surface. Often the loops are so dense that a secondary blotch is the result. Because upper- and lower-surface corridor segments often cross, the mine obtains a strange array of transparant patches. There is no association with the midrib. Frass in strings and thread fragments. Pupation outside the mine; exit slit in upper epidermis.

Mine not associated with the veins or midrib of the leaf (It is this character which enables distinction from another Agromyzid pest species - Liriomyza huidobriensis). The larvae may leave one leaf (if not large enough) and enter another leaf, via the petiole). It exits the leaf to pupate through a semi-circular slit in the upper surface of the leaf.

Polyphagous. On 119 plant genera in 31 plant families of which only 4 plant genera in 2 plant families, but not yet on Alisma, in Britain. Local, probably introduced to Britain. Widespread in continental Europe particularly in Botanical Gardens and glasshouses. Also recorded in Egypt.

Liriomyza bryoniae (Kaltenbach, 1858) [Diptera: Agromyzidae].

1e > Leaf-miner: The mine starts with a broad corridor. Later a broad blotch, not determined by heavy veins. The mine is full depth and very transparent. The colour in the end is reddish-brown, making mined plants very conspicuous, even from a distance. Frass irregular. Often several larvae in a mine.

On Alisma plantago-aquaticain Britain plus Luronium natans and Sagittaria sagittifolia, elsewhere. Widespread in Britain and continental Europe. Also recorded in the Republic of Ireland.

Bagous alismatis (Marsham, 1802) [Coleoptera: Curculionidae].