Echinops leaf miner
Globe thistle (Echinops) foliage can be mined by the larvae of a fly feeding within the leaves.
Quick facts
Scientific name Phytomyza bipunctata
Plants affected Globe thistle (Echinops)
Main cause Larvae of a leaf-mining fly tunnelling in the foliage
Timing Spring and summer
What is echinops leaf miner?
The fly belongs to the family Agromyzidae, there are several hundred species in this family known to occur in Britain and many are leaf miners as larvae. More information on Agromyzidae is available from the Agromyzidae recording scheme.
Around 900 insect species, including some beetles, sawflies and moths create leaf mines as larvae in Britain. More information about some for these insects can be found at The leaf and stem mines of British flies and other insects.
Symptoms
The adult flies are ash grey and about 2mm long. They feed by rasping the leaf surface, causing many small pale spots on the upper leaf surface. More significant mines are caused by the creamy white larvae. They eat the internal tissues of the leaves and cause whitish brown discoloured blotches. The mines typically have a pale edge around the darker brownish centre.
There are probably at least two generations during the summer and by August leaves can be affected by several mines.
Management
Echinops plants will survive and produce flowers, even when there is extensive leaf mining, so it is not necessary to control this insect. Leaf miners can be part of a healthy balanced garden, most species will have natural enemies including parasitoid wasps. Birds such as blue tits can sometimes open mines to consume the larvae within.
Biology
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