1150 Accepted by Z.-Q. Zhang: 21 Feb. 2006; published: 14 Mar. 2006 1 ZOOTAXA ISSN 1175-5326 (print edition) ISSN 1175-5334 (online edition) Copyright © 2006 Magnolia Press Zootaxa 1150: 1–17 (2006) www.mapress.com/zootaxa/ New fungus-feeding thrips (Thysanoptera–Phlaeothripinae) from tropical Australia LAURENCE A. MOUND 1 & KAMBIZ MINAEI 2 1 CSIRO Entomology, GPO Box 1700, Canberra ACT, Australia 2601. E-mail: Laurence.Mound@csiro.au 2 Plant Protection Department, College of Agriculture, Tehran University, Iran Abstract Three new genera and seven new species of fungal-feeding thrips are described from the northern, tropical zone of Australia. Majerthrips barrowi gen. et sp. n. is a large species exhibiting polymorphism associated with wing development and sex, whereas Senithrips psomus gen. et sp. n. is a minute monomorphic species with little sexual dimorphism. Also monomorphic is Jacotia rhodorcha sp.n., the fourth species described in this genus from Australia. These three were all taken during a biodiversity survey of Barrow Island, Western Australia. Structural variation in Streptothrips tribulatius sp. n. from Cape Tribulation, Queensland, confirms the existence of dimorphism in this genus between winged and wingless individuals. Stomothrips mouldeni differs from the single described species in this genus in having the mouth cone directed ventrally not posteriorly; it was collected from Cycas pruinosa in the north of Western Australia. Also in this area but living at the base of Triodia grasses, Apostlethrips apostus and A. pygus gen. et spp. n. are remarkable amongst the Eurythrips group of leaf-litter phlaeothripines in lacking sense cones on antennal segment III, and lacking tergal wing retaining setae in macropterae, also in the setose abdominal apex. Key words: Thysanoptera, Phlaeothripidae, Australia, new genus, new species, fungus feeding, polymorphism Introduction The number of described Thysanoptera species recorded from Australia has risen sharply in recent years, from 287 in 1970 (CSIRO Textbook) to 685 in 2005 (see checklist published by the Australian Biological Resources Study http://www.deh.gov.au/ biodiversity/abrs/online-resources/fauna/afd/group.html). Much of this descriptive effort has been, and continues to be, targeted at particular genera or at groups of species associated with particular host plants, because such approaches lead to a better