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The invasive Australian redback spider, Latrodectus hasseltii Thorell 1870 (Araneae: Theridiidae): current and potential distributions, and likely impacts

Vink, Cor J., Derraik, José G. B., Phillips, Craig B., Sirvid, Phil J.
Biological invasions 2011 v.13 no.4 pp. 1003-1019
Latrodectus, biodiversity, cities, climate, feeds, habitats, human health, indigenous species, invasive species, invertebrates, population distribution, urban areas, Japan, New Zealand
Populations of the Australian redback spider, Latrodectus hasseltii Thorell 1870, were first recorded in New Zealand in the early 1980s and in Osaka, Japan in 1995. Reliable records suggest that naturalised populations of L. hasseltii in New Zealand are present only in Central Otago and New Plymouth. In Central Otago, L. hasseltii feeds on endangered invertebrates, such as Prodontria modesta (Broun 1909). Latrodectus hasseltii is also a hazard to the New Zealand endemic L. katipo through interbreeding and competitive displacement. CLIMEXTM was used to model the potential global distribution of L. hasseltii based on current climate, and using ArcGIS® 9.2, areas of suitable climate in New Zealand were overlaid with favourable habitats to identify areas most suitable for L. hasseltii establishment. In addition, shelter that urban areas offer L. hasseltii were modelled in CLIMEX and incorporated into ArcGIS to produce maps indicating cities and built up areas where the species could establish. The presence of L. hasseltii in New Zealand and Japan, and its possible spread to other areas, is of human health significance, and the species may also impact on native biodiversity.