Genista [Fabaceae]

GENISTA. Greenweeds, Petty Whin and Broom. [Fabaceae]

Eleven species of Genista are recorded in Britain. These include the native Hairy Greenweed (G. pilosa) and Petty Whin (G. anglica) and Dyer's Greenweed (G. tinctoria).

Two Diptera miners, the agromyzids Agromyza johannae and Agromyza pulla, are recorded on Genista in Britain.

Elsewhere the agromyzid Agromyza pulla is recorded mining Genista and the agromyzid Hexomyza sarothamni is recorded galling twigs of Genista.

Eight non-Diptera miners are recorded on Genista in Britain (see below).

A key to the European miners, based on characteristics of the mines, immature stages and where relevant the larval cases, recorded on Genista including Chamaespartium (=Genistella) and Pterospartum is provided in Bladmineerders van Europa. This includes Agromyza johannae, Agromyza pulla, Cnephasia asseclana, Cnephasia incertana, Cnephasia stephensiana, Coleophora colutella, Coleophora genistae, Coleophora hartigi, Coleophora onobrychiella, Coleophora sardocorsa, Coleophora saturatella, Coleophora trifariella, Coleophora vibicella, Leucoptera genistae, Leucoptera laburnella, Micrurapteryx kollariella, Mirificarma cytisella, Oryxolaemus flavifemoratus, Phyllonorycter cerasinella, Phyllonorycter estrela, Phyllonorycter etnensis, Phyllonorycter fraxinella, Phyllonorycter genistella, Phyllonorycter juncei, Phyllonorycter triflorella, Phyllonorycter staintoniella, Syncopacma albipalpella, Syncopacma cincticulella, Syncopacma suecicella, Syncopacma vinella but not Coleophora glaseri, Coleophora pterosparti or Leucoptera andalusica.

N.B. The key to mines below includes mines recorded on Genista, Spartium and Ulex (Fabaceae).

Key for the identification of the mines of British Diptera recorded on
Genista, Spartium and Ulex

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 > Initially a linear mine, normally adjoining leaf-margin and running towards apex of leaf, then turning and widening into a blotch in area of mid-rib. Puparium reddish-orange

On Cytisus, Genista, Lupinus, Spartium and Ulex in Britain and elsewhere. Common in gardens in Britain where Cytisus is frequently cultivated. Widespread in continental Europe.

Agromyza johannae Meijere, 1924 [Diptera: Agromyzidae].

1b > Leaf mine. An initial linear mine, which later develops into a blotch.

On Genista and Spartium, but not yet on Ulex, in Britain and elsewhere. Widespread in southern Britain and continental Europe.

Agromyza pulla Meigen, 1830 [Diptera: Agromyzidae].

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

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 > Miner and case bearer. The larva lives outside the mine, protected by a case, and feeds on the underlying plant tisses via a hole cut in the epidermis. Mine does not contain frass (Coleophora species)

1b > Miner, but not a case-bearer, although it may live sandwiched between two more or less circular sections cut from the leaf in later instars e.g. Incurvaria species. The larva lives mainly inside the mine. Mine usually contains frass

2a > Leaf-miner and case-bearer: The larva feeding on the leaves, and sometimes the flowers. The leaves are blanched by the feeding and the species often feeds gregariously, becoming a pest. The larval case is built in a distinctive herringbone-like fashion, and is sometimes likened to a spikelet of certain grasses (UKMoths). Lobe case. Each lobe consists of a mined leaflet, that has been sliced open at one side. The lobes are attached alternatively dorsally and ventrally, resulting in a sharp dorsal and ventral keel. The complete case strongly resembles a grass spikelet, like of Bromus. Mouth angle 20-40° (Bladmineerders van Europa).

Case of Coleophora genistae on Genista anglica
Image: Willem Ellis (Bladmineerders van Europa).

Recorded on Genista in Britain and elsewhere. Widespread in Britain and continental Europe.

Coleophora genistae Stainton, 1857 [Lepidoptera: Coleophoridae].

2b > Leaf-miner and case-bearer: Very untidy, bivalved, lobe case of 7-8 mm. The mouth angle is 90°, causing the case to be perpendicular to the leaf (Bladmineerders van Europa)

Recorded on Cytisus and Genista in Britain and Cytisus, Genista, Spartium and Ulex elsewhere. Britain including West Kent and South Gloucester. Widespread in continental Europe.

Coleophora saturatella Stainton, 1850 [Lepidoptera: Coleophoridae].

2c > Leaf-miner and case-bearer: Larva in a huge (19 mm) shining black tubular silken case; mouth angle 60°. The end of the case is strongly rolled in (remnant of the youth case) and bears a small pallium (Bladmineerders van Europa) The final case is the largest of any coleophorid in the UK, being 19mm long. The anal end of this case incorporates the remains of the spiral first case and is hooded in a pallium (British leafminers).

Recorded on Genista in Britain and Chamaespartium, Genista and Vicia elsewhere. Southern England. Widespread in continental Europe.

Coleophora vibicella (Hübner, 1813) [Lepidoptera: Coleophoridae].

3a > Bark-mine: A gallery in the bark of the food plant generally mining upwards, similar to that of Trifurcula immundella, which usually mines downwards (British leafminers). The mines are very hard to detect, but in late spring, the small white pupal cocoons are easy to spot among the dark stems (UKMoths).

Recorded on Cytisus and Genista in Britain. Hosts elsewhere unknown. Widespread in Britain, Ireland and continental Europe.

Leucoptera spartifoliella (Hübner, 1813) [Lepidoptera: Lyonetiidae].

3b > 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 Genista, in Britain. Recorded on numerous genera and species of plant families including Genista elsewhere. Widespread in Britain and continental Europe. Also recorded from the Channel Is.

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

3c > Leaf-miner: An irregular gallery filled with greenish frass, leading to a circular or oval blotch with blackish frass arranged in a spiral fashion (British leafminers). The very first part of the mine is a densely contorted corridor of about 2 mm long, that quickly turns brown. It is followed by a more or less straight corridor of c. 10 mm, entirely filled with greyish green frass. This suddenly widens into a round blotch that during its expansion overruns the earlier corridor and in the end may occupy half of a Laburnum leaflet. The frass, greenish at first, black later, is deposited in the bloth in roughly concentric arcs, glued to the upper epidermis. Pupation external, exit slit in upper epidermis (Bladmineerders van Europa).

Recorded on Cytsisus, Genista, Laburnum, Lupinus and Piptanthus in Britain and Astragalus, Chamaecytisus, Genista, Laburnum, Laburnocytisus, Lupinus and Petteria elsewhere. Widespread in Britain and continental Euorpe. Also recorded in the Republic of Ireland.

Leucoptera laburnella (Stainton, 1851) [Lepidoptera: Lyonetiidae].

3d > Leaf-miner: Upper-surface tentiform mine (according to Hering, 1957a, mostly lower-surface in Laburnum). The mine is strongly contracted, almost folding the leaflet to a pod and concealing the mine. Pupa in the mine in a flimsy cocoon. Frass in a corner of the mine (Bladmineerders van Europa).

Recorded on Genista in Britain and Chamaecytisus, Cytisus, Genista and Laburnum elsewhere. Britain including West Cornwall. Widespread in continental Europe.

Phyllonorycter staintoniella (Nicelli, 1853) [Lepidoptera: Gracillariidae].

3e > Leaf-miner: The larva lives among spun leaves, mining them from this position by gnawing irregular, more or less oval holes in the epidermis and eating from there the leaf tissue. Obviously, the mines contain little or no frass (Bladmineerders van Europa).

Mine of Syncopacma albipalpella on Genista anglica
Image: Rob Edmunds (British leafminers)

Recorded on Genista in Britain and elsewhere. Britain including East Sussex. Widespread in continental Europe.

Syncopacma albipalpella (Herrich-Schäffer, 1855) [Lepidoptera: Gelechiidae].

3f > Leaf-miner: The larva feeds between spun leaves, often mining them (Bladmineerders van Europa).

Recorded on Genista in Britain and elsewhere. Britain including West Cornwall. Widespread in continental Europe.

Syncopacma suecicella (Wolff, 1958) [Lepidoptera: Gelechiidae]


	Last updated 01-Feb-2012 Brian Pitkin