Three new Australian species of Trioza Foerster (Hemiptera: Triozidae) with a remarkable adaptation to oviposition on articulate branchlets of Allocasuarina (Casuarinaceae)

Abstract

Three new species of jumping plant bugs (Hemiptera: Psylloidea) are described from Allocasuarina (Casuarinaceae) from southern and eastern Australia. These are Trioza kentae Taylor sp. nov., T. percyae Taylor sp. nov. and T. tricornuta Taylor sp. nov. The female proctiger of two species, T. kentae Taylor sp. nov. and T. tricornuta Taylor sp. nov., has a three-pronged apex, thought to be a remarkable morphological adaptation to assist with oviposition into the furrows of the branchlets or ‘articles’ of their host plant. It is postulated that the highly modified processes are used to ‘anchor’ the female proctiger during oviposition, where the medial prong positions the female ovipositor within a ‘furrow’ and the lateral processes straddle the ‘phyllichnia’ of the host plant ‘article’. In this way, eggs may be deposited within the furrow, thereby protected from desiccation and predation. In T. percyae Taylor sp. nov., the apex of the female proctiger is without any such structure. These are the first species of Trioza to be described from the Casuarinaceae.