Leptocybe invasa Fisher & LaSalle, a new genus and species of Eulophidae, displays thelytokous reproduction, forming typical bump-shaped galls on the leaf midribs, petioles and stems of new growth of several Eucalyptus species. Presently, this wasp occurs in large areas in the Middle East, the Mediterranean and Africa, and is a serious pest in young plantations. Heavy galling prevents further development of the infested growth. Leptocybe invasa is only known from females. Mean length of a gall containing a single wasp is 2.1 mm, leaves of intensively growing trees may carry over 50 galls per leaf. Mean development time from oviposition to emergence is 132.6 d in room temperature. In Israel the wasp produces two or three overlapping generations annually. Mean survival time for wasps fed with honey and water is 6.5 days. Ten species were found to be suitable hosts in Israel:

Two species of Tetrastichinae (Hymenoptera: Eulophidae) from Australia are described as parasitoids of Leptocybe invasa Fisher & La Salle: Quadrastichus mendeli Kim & La Salle sp.nov. and Selitrichodes kryceri Kim & La Salle sp. nov. These parasitoids were introduced to Israel as part of a biological control program to counter the severe levels of damage caused by L. invasa to Eucalyptus plantations throughout the Mediterranean Basin. The biology of these species, as well as their potential as biological control agents, is discussed. Both species are now successfully established in Israel. The parasitoids were collected from L. invasa galls on 3–4 year old Eucalyptus tereticornis trees in central west Queensland, between Gympie and Hervey Bay, and on the Atherton Tableland. Both species are small (about 1 mm in length), solitary, and apparently ectoparasitic wasps. S. kryceri is biparental whereas Q. mendeli is uniparental. Maximum survival (~ 6 days at 25°C) for both species was obtained when they were fed with honey solution. S. kryceri and Q. mendeli successfully parasitized approximately 2.2 and 2.5 gall units per day, respectively. Both species developed on both young and mature host larvae. L. invasa may be considered as an early colonizer of regenerated young stands in Australia, which may imply that its parasitoids will display a similar fast-tracking behavior with respect to their host in its invasive range. The generic status of Selitrichodes is reinstated, with Epomphaloides and Zagrammosomoides placed as new synonyms of Selitrichodes.

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