Revision of the Australian species of Pleistodontes (Hymenoptera: Agaonidae) fig-pollinating wasps and their host-plant associations

The Australian species of Pleistodontes, fig-pollinating wasps, are revised. In Australia, 14 species of Ficus belonging to the Urostigma sect. Malvanthera are known. From these Ficus, 17 species of Pleistodontes are recorded, of which seven are described as new. All type material has been examined and four new specific synonymies are proposed. One species, P. regalis Grandi, is resurrected from synonymy, while another, P. nitens (Girault) is redescribed. A key to females of Australian Pleistodontes is provided. All species are defined by means of full morphological descriptions, diagnosis, SEM photographs and drawings. Lectotypes are designated for nine species. The known distribution of each species is also given. Host plant (Ficus) associations are re-assessed in the light of this work and the recent revision of Australian Ficus sect. Malvanthera. In most cases there is a one-to-one relationship between Ficus and Pleistodontes species; however, three notable exceptions are discussed. Finally, our morphological study suggests strongly that the genus Pleistodontes includes some species that pollinate fig flowers actively and others that effect only passive pollination.