18. Potential Biological Control Agents for Leafy Spurge Found in Southern France.  R. Sobhian

Numerous natural enemies have been found in southern France on Euphorbia spp., during 1992 and 1993. Among them, the following six species seem to be promising for biological control of leafy spurge in the USA:

1. A gall midge, Spurgia capitigena found on Euphorbia esula, in under study in Bozeman, MT. Its host specificity also is under study by M. Cristofaro in Rome and by myself in France. So far, there have been no surprises and the first weed insect from France may be released in the USA during 1995.

2. A gall mite, Phyllocoptes nevadensis, found on E. cyparissias. Preliminary host specificity tests showed that E. esula from USA is a susceptible host for the mite, while poinsetia, croton, and E. corollata were not attacked.

3. A leaf beetle, Aphthona occitana, found on E. segetalis and E. characias. According to Dr. M. Biondi, the taxonomist in this group, this species has been reported on Euphorbia spp. in Europe, and should be specific to the genus Euphorbia.

4. and 5. Two new species of Agromyzidae, Liriomyza n. sp. and Ophiomya n. sp. According to K.A. Spencer, only 4% of the known Agromyzidae are polyphagous. Thus the possibility that the host range of these species is restricted to the genus Euphorbia is very high. Liriomyza is a leaf miner; Ophiomya is a stem miner.

6. A Tortricide moth, Acroclita subsequana, found on E. characias. The species has been reported only from Euphorbia spp. and has a very wide distribution, from England through Europe to the former USSR (it is under study by L. Fornasari).