A review of the oribatid mite family Nothridae in Australia, with new species of Novonothrus and Trichonothrus from rain forest and their Gondwanan biogeographical affinities (Acari: Oribatida)

Abstract

The Nothridae of Australia hitherto consisted of the semi-cosmopolitan Nothrus anauniensis, Novonothrus flagellatus and an un-named Novonothrus species. This paper contains additional records of N. anauniensis and descriptions of five new species of Novonothrus, including immatures (N. barringtonensis sp. nov., N. coronospinosus sp. nov., N. glabriseta sp. nov., N. nothofagii sp. nov. and N. silvanus sp. nov.), a genus known from Australia, New Zealand and Chile. A key to Novonothrus is provided and the genus redefined. A second species of Trichonothrus (T. hallidayi sp. nov.), is described, representing a new generic record for Australia: Trichonothrus was previously known only from South Africa. Supplementary descriptions are given for Novonothrus flagellatus Hammer, 1966 and Trichonothrus austroafricanus Mahunka, 1986. The Australian record of the former species is based on a misidentification of the species described herein as N. glabriseta sp. nov. and N. flagellatus appears to be confined to New Zealand. Three species groups are proposed for Novonothrus: Barringtonensis (N. barringtonensis, N. nothofagii and N. silvanus) from central New South Wales and Victoria; Puyehue (N. glabriseta from Tasmania, N. puyehue, N. covarrubiasi and N. kethleyi from Valdivian temperate rain forest in Chile) and Flagellatus (N. coronospinosus from northern New South Wales and N. flagellatus from native forest, including Nothofagus, in New Zealand). Novonothrus and Trichonothrus show a relict Gondwanan distribution and are associated with indigenous wet forests. In Australia, members of these genera have been recorded mostly from cool tem-perate Nothofagus rain forest. The relatively high diversity of sexual species of Nothrina in Australian temperate rain forests is contrasted with high diversity of thelytokous parthenogenetic species in temperate Northern Hemisphere localities and is discussed in relation to differences in palaeoclimate and environmental history.