Black widow spider
Theridiidae - Latrodectus mactans
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What does it look like?

The black widow spider Lactrodectus mactans can be recognised by the red hourglass marking on its ventral side of the abdomen. The black widow spider is about 2.5 – 3.8 cm in body length and is a lustrous black colour except for the red coloured hourglass marking. The male usually has light streaks on its abdomen and is much smaller than the female. The female eats the male after mating. She hangs belly upward and rarely leaves the web.

Why is it a problem?

The black widow is not aggressive. It will, however, bite instinctively when touched or pressed. The potency of the black widow venom is well documented. All encounters with humans and animals can be attributed to the female. Death due to widow venom is rare and in untreated patients symptoms rarely persist for more than two days.

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