Plant hosts and parasitoid associations of leaf mining flies (Diptera : Agromyzidae) in the Canberra region of Australia

Many leaf mining flies (Diptera: Agromyzidae) are important economic pests of agricultural crops and ornamental plants, and species-rich hymenopteran parasitoid complexes are important in their control. Australian agromyzids are poorly studied, and little is known about their host plants, ecology or natural enemies. We surveyed native and naturalised species of leaf mining flies in Tallaganda National Park, New South Wales and the Australian Capital Territory. Malaise and emergence trapping in Tallaganda yielded 70 agromyzid specimens from six species in four genera: Cerodontha Rondani, Liriomyza Mik, Phytoliriomyza Hendel and Phytomyza Fallen. Of the six species collected, three are Australasian species, two are naturalised species introduced from Europe and one could not be determined to species. The Australian Cerodontha (Cerodontha) milleri Spencer represented most of the individuals caught in both Malaise and emergence traps. A total of 163 agromyzid and 98 parasitic wasp specimens were reared from plant samples with agromyzid mines in the Canberra region. Most agromyzids and parasitoids were reared from the weed Sonchus oleraceus L. (Asteraceae). All the agromyzids reared belonged to two introduced species of the genera Phytomyza and Chromatomyia Hardy. The biodiversity of parasitic wasps reared was high with 14 species from seven genera and three families. Hemiptarsenus varicornis (Girault) (Eulophidae), a widespread Old World agromyzid parasitoid, was the most numerous parasitoid reared in our survey.