Short introduction to Agromyzidae

The Agromyzidae (mining flies) are a highly diverse dipteran family of exclusively phytophagous species. The world fauna consists of about 2,750 species (Henshaw and von Tschirnhaus, in prep). Of these some 110 species are known to occur on cultivated crops and to cause occasional damage. However, a number of species are of particular importance, especially those feeding on Fabaceae and some horticultural plants.
All known agromyzids are internal feeders of living plant tissue. They exhibit an array of different feeding habits such as leaf-mining, stem-mining and -tunneling, cambium-mining and parasitism of flower heads and fruits. Leaf-mining is generally the most widespread feeding behaviour among Agromyzidae. By consuming and damaging photosynthetically active tissue on the leaf surface, the larva reduces the plant metabolism and vigor. The aesthetic damage by the well-visible feeding traces (mines) can reduce the value of products or even render them unmarketable. That is particularly important for ornamental crops. Stem miners can be even more dangerous when they affect the vascular tissue in the stems and may stunt the growth of the host plant. Mines and punctures caused by feeding and ovipositing females can facilitate the plants' infestation by fungi and bacteria.
If they occur in large numbers on cultivated crops, the larvae of agromyzid flies can cause either significant yield reduction or even large-scale plant mortality. Thus, the economic loss due to Agromyzidae can be substantial. Recently, the problem has further aggravated by accidental introduction of agromyzids (e.g. some Liriomyza species) into new regions; thus some major pests are nowadays nearly worldwide distributed.
Reliable identification of the pest species is an important prerequisite for effective control and quarantine measures especially if Integrated Pest Management or biological control is applied. Taxonomic confusion is a major problem in controlling pest species (Parrella and Keil, 1984). This is, because closely related species may have a different lifestyle and different host preferences. Agromyzidae are considered difficult to identify because of their uniformity and small body sizes (wing length normally 2-4 mm). On many plants several similar species may occur together.
By making available taxonomic and biological data, this CD-ROM aims to contribute to an improvement of the management of pest-agromyzids.