The hyperdiverse oribatid mite genus Scapheremaeus (Acari: Oribatida: Cymbaeremaeidae) in Australia, with descriptions of new species and consideration of biogeographical affinities

Abstract

This paper contains descriptions of thirteen new Australian species of Scapheremaeus Berlese, 1910, belonging to the species groups Carinatus from New South Wales and Victoria (S. alisonae sp. nov., S. allmani sp. nov., S. nivalis sp. nov., S. tuberculosus sp. nov. and S. zephyrus sp. nov.), Patella from Western Australia and Tasmania (S. baylyi sp. nov. and S. tegulatus sp. nov.), Petrosus from New South Wales, Tasmania, Victoria and Western Australia (S. bulbosensillatus sp. nov., S. euthemellus sp. nov., S. minjambuta sp. nov., S. notoverrucatus sp. nov. and S. truncatus sp. nov.) and Emarginatus from Queensland (S. walteri sp. nov.), Only members of the predominantly Neotropical and Australasian Carinatus species-group have been described from Australia hitherto, and Australian species constitute a third of this group. The Patella species-group is mostly Afrotropical (four spp.), with one Palaearctic and three Australasian species, including the two new species described herein. The Petrosus species-group, previously known from three Palaearctic, two Oriental and one Neotropical species, is now dominated by five new Australian species described herein. The Emarginatus species-group contains one species each from Australia, New Zealand, Java and Cuba. A key to Australian species is provided. The genus Scapheremaeus contains some 112 species, and can be considered hyperdiverse by oribatid standards. Morphological traits are considered that may relate to the ecological diversification and adaptive radiation of Scapheremaeus, particularly those related to species living on leaves and stems within rainforest canopies.