HIRSCHFELDIA. Hoary Mustard. [Brassicaceae]

Only one species of Hirschfeldia, Hoary Mustard (H. incana) is recorded in Britain. It is introduced.

No Diptera miners are recorded on Hirschfeldia in Britain.

Elsewhere the polyphagous agromyzids Chromatomyia horticola and Liriomyza strigata and the drosophilid Scaptomyza flava are recorded mining Hirschfeldia.

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

Elsewhere two British non-Diptera miners are recorded on Hirschfeldia (see below).

A key to the European miners, based on characteristics of the mines, immature stages and where relevant the larval cases, recorded on Hirschfeldia is provided in Bladmineerders van Europa. This includes Chromatomyia horticola, Liriomyza brassicae, Liriomyza strigata, Liriomyza xanthocera, Scaptomyza flava, Ceutorhynchus minutus, Cnephasia incertana, Phyllotreta nemorum and Plutella xylostella.

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

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: Rather small, untidy, full depth, often branched corridor, often close to the leaf margin. Sides irregularly eaten out. Frass in a greyish-green central line that is interrupted from time to time, sometimes partly in strings. In times of rain the frass may run out and appear greenish. Usually several mines in a leaf (Bladmineerders van Europa). The legless larva is rather shapeless, with a well-sclerotised head. The body is whitish; head greyish brown with Y-shaped lighter marking. Pronotum with a pair of brownish shields. The mandibles have two teeth (Bladmineerders van Europa).

Mine of Ceutorhynchus minutus on Raphanus sativus Image: Willem Ellis (Bladmineerders van Europa)

Recorded on numerous genera and species of Brassicaceae, Capparaceae, Resedaceae and Tropaeolaceae, including Cochlearia, but not yet on Hirschfeldia, in Britain and Hirschfeldia elsewhere. Widespread in Britain and continental Europe. Also recorded in the Republic of Ireland.

Ceutorhynchus minutus (Marsham, 1802) [Coleoptera: Curculionidae]

1b > Leaf-miner: In the first instar the larva mines the leaves, forming short, irregular, blotch-like mines, but in later instars it lives externally, feeding in spun leaves and often twisting those of tender shoots. Larval head light-brown or yellowish brown, edged with black postero-laterally, ocellar area blackish; prothoracic plate black edged with whitish anteriorly; abdomen dull dark green; pinacula distinct, black, sometimes brownish but with black bases to setae; anal plate large, black (Bradley et al., 1973). Small, full depth mine without a definite shape; little frass. Some silk is deposited in the mine. The larva soon leaves the mine and continues feeding among spun leaves (Bladmineerders van Europa).

Recorded on numerous genera and species of plant families, but not yet on Hirschfeldia, in Britain. Recorded on numerous genera and species of plant families including Hirschfeldia elsewhere. Widespread in Britain and continental Europe. Also recorded from the Channel Is.

Cnephasia incertana (Treitschke, 1835) [Lepidoptera: Tortricidae]