First winter record of Latrodectus mirabilis (Araneae: Theridiidae) in arid Patagonia: A consequence of climate change and urbanization?

Cases of araneism reported in the province of Chubut (Argentina) have tripled in the last two decades, and almost 80 % of them involve Latrodectus mirabilis (Holmberg) (Araneae: Theridiidae). According to descriptions of the life cycle of this species in Argentina, the low temperatures typical of autumn-winter cause the death of all adult spiders, so that no adult specimens of L. mirabilis are observed in winter.