Black widow spiders (family 
Theridiidae, genus 
Latrodectus) are notorious for their 
neurotoxic[?] venom.  They are large spiders found throughout the world and are commonly associated with urban habitats or agricultural areas.  Although the common name 'black widow spider' is applied to several members of the 
Latrodectus genus, there are 31 recognised 
species in the genus and include the Australian red-back and brown widow.
 
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