Tasmanian Antarctoperlaria (Plecoptera)

Abstract

There are two species of Eusthenia, which are distinguishable in all stages. The female Crypturoperia paradoxa is described, as are adults of Tasmanoperla larvalis, comb. nov. There are two species of Leptoperla, which are easily distinguished as adults and larvae and are different from mainland species. Cardioperla is shown to be monotypic, Riekoperla triloba to be strictly Tasmanian, and a single female that is possibly R. rugosa is recorded from the state. Trinotoperla has three Tasmanian species, one new, and Dinotoperla four, two new. It seems probable that individuals of D. fusca are really elderly females of D. serricauda. There are only single new records of Newmanoperla thoreyi and Illiesoperla australis from the state. The reasons why so few, possibly six, species of Plecoptera occur on both sides of Bass Strait are examined in the light of the known history of the biota and of the strait itself. It is concluded that the isolation of Tasmanian stoneflies has been a long one, and that land bridges to Wilson's Promontory have provided routes for only a few inhabitants of warm lowland streams.