Inula [Asteraceae]

INULA. Ploughman's-spikenard, Golden-samphire and Irish Fleabane. [Asteraceae]

Ten species of Inula are recorded in Britain. These included the native Ploughman's-spikenard (I. conyzae), Golden-samphire (I. crithmoides) and Irish Fleabane (I. salicina).

Three Diptera miners, the agromyzids Chromatomiya 'atricornis', Chromatomyia syngenesiae and Phytomyza conyzae, are recorded on Inula in Britain, and two of these also occur on Pulicaria in Britain.

The agromyzid Melanagromyza eupatorii bores the stems of Inula in Britain and elsewhere.

Elsewhere the polyphagous agromyzids Chromatomyia horticola, Chromatomyia syngenesiae, Phytomyza conyzae and Liriomyza strigata are recorded mining Inula.

Elsewhere the agromyzid Napomyzxa lateralis is recorded boring stems of Inula.

Four non-Diptera mines, are recorded on Inula in Britain (see below).

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

N.B. The key to mines below includes mines recorded on Inula and Pulicaria (Asteraceae).

Key for the identification of the mines of British Diptera recorded on
Inula and Pulicaria

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: Mine linear, whitish, both upper and lower surface. Pupation internal, at the end of the mine with the anterior spiracles projecting through the epidermis (Spencer, 1976: 433). Upper-surface, less often lower-surface corridor. Frass in isolated grains. Pupation within the mine, in a, usually lower-surface, pupal chamber (Bladmineerders van Europa). A long whitish upper surface corridor, which eventually goes lower surface (British leafminers).

Two highly polyphagous species of Chromatomyia, with indistinguishable mines, have been recorded in Britain. These are syngenesiae (Hardy) and horticola (Goureau) which can only be distinguished by the male genitalia. Both are polyphagous and widespread in Britain and elsewhere, although syngenesiae is almost entirely restricted to Asteraceae (see also 'atricornis').

Chromatomyia horticola is recorded on 55 plant genera in 19 families in Britain but not yet on Inula in Britain.

Chromatomya syngenesiae is recorded in Britain on 27 plant genera in the family Asteraceae and many more genera elsewhere, including Inula in Britain.

Chromatomyia horticola (Goureau, 1851) [Diptera: Agromyzidae].
OR
Chromatomyia syngenesiae Hardy, 1849 [Diptera: Agromyzidae].

1b > An irregularly linear mine which can be both on the upper and lower leaf surface. Pupation takes place either at the end of the mine in an exit slit cut in the leaf or on the ground. Puparium black or dark brown

On Inula and Pulicaria in Britain and additional genera of Asteraceae elsewhere. Widespread in Britain. Also recorded in the Republic of Ireland. Widespread in continental Europe and particularly common in the Mediterranean area

Phytomyza conyzae Hendel, 1920 [Diptera: Agromyzidae].

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

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 > Stem miner

1b > Leaf miner

2a > Leaf-miner and case-bearer: The larva makes at least two cases and leaves the empty case by the cut out leaf section. The early cases are compressed with keels, dorsally and laterally. Later cases are more tubular and hairy (from the hairy leaves, used to make the case) (British leafminers). Larva in a spathulate leaf case. It is 10-12 mm long, straght, brown, tubular, patently hairy (depending on the hostplant), bivalved. The mouth angle is rather variable, usually around 45°. An unusual character of this species is that after each moult the larva makes a new case; the old, vacated case is left at the place where the new one is made, at the leaf margin (Bladmineerders van Europa).

Recorded on Eupatorium, Inula and Pulicaria in Britain and elsewhere. Mainly distributed in southern England and Wales. A colony has also been located in York, so it may occur elsewhere. Widespread in continental Europe.

Coleophora conyzae Zeller, 1868 [Lepidoptera: Coleophoridae].

2b > Leaf-miner and case-bearer: Larva mines leaves. On Eupatorium the case is extended at the anal end by adding silk and widened by cutting a ventral gusset. On Inula the case is firstly extended by adding rings of leaf-cuticle at the oral end, before reverting to the method used when on Eupatorium. The full-grown case is 10 mm long (British leafminers). A slender tubular silken case, about 10 mm long, straw coloured, three valved. Mouth angle about 30° (Bladmineerders van Europa).

Recorded on Cirsium, Eupatorium, Inula and Pulicaria in Britain and Achillea, Anthemis, Carduus, Cirsium, Eupatorium, Inula, Leucanthemum, Pulicaria and Tanacetum elsewhere. Widespread in England. Also recorded in Republic of Ireland. Widespread in continental Europe.

Coleophora follicularis (Vallot, 1802) [Lepidoptera: Coleophoridae].

2c > Leaf-miner and case-bearer: The larva builds a 'pistol case' (UKMoths). The mature case is around 15mm long with a slightly swollen middle region, being palest at the anal end (British leafminers). Larva in a slender tubular silken case. The case is about 15 mm long, yellow-grey, and trivalved. The mouth angle is about 0°-10°, causing the case to lie flat on the leaf (Bladmineerders van Europa).

Recorded on Inula and Pulicaria in Britain and Eupatorium, Inula and Pulicaria elsewhere. A scarce and very local species which has a small number of tiny colonies in the south of England, principally in Hants and the Isle of Wight. Widespread in continental Europe.

Coleophora inulae Wocke, 1877 [Lepidoptera: Coleophoridae].

3a > Leaf-miner: Mines the lower leaves, making them hollow. The mine is along the midrib and broadens into a blotch (British leafminers). One or several broad corridors, radiating from the leaf base, often along the midrib, towards the leaf tip widening into a roundish blotch, not containng any frass. The larva, that seems to feed only at night, retreats during feeding pauses in the leaf base and is invisible then. Often two larvae in a mine. Pupation in a little separate mine (pupal chamber) (Bladmineerders van Europa).

Recorded on Inula conyzae in Britain and elsewhere. Southern England. Widespread in continental Europe.

Digitivalva perlepidella (Stainton, 1849) [Lepidoptera: Acrolepiidae].

3b > Leaf-miner: Rather narrow corridor, untidy and sometimes branched, starting from the base of the leaf, in particular the midrib. Sides of the corridor irregularly eaten out, not really parallel. Frass mostly present, and then in a central line. The legless larva is capable of leaving the mine and start a new one elsewhere. These later mines are much broader, and the frass is scattered irregularly. (Bladmineerders van Europa.

Host plants unknown in Britain. Recorded on numerous genera and species in several plant families, including Inula, elsewhere. Recorded in southern England. Widespread in continental Europe.

Orthochaetes insignis (Aube, 1863) [Coleoptera: Curculionidae].


	Last updated 01-Feb-2012 Brian Pitkin