Female Black Widow, Latrodectus mactans. Ventral view, showing the famous red hourglass. Black Widows prefer damp places. This one lives under the watering trough in a horse pasture across the road from me. The neighbor found it while flipping the trough to empty it in order to clean it and refill it. This specimen is a beautiful one and was most cooperative for the camera. The venom of the female Latrodectus macrons is a potent neurotoxin, but bites are rare--the animal must be strongly provoked to bite a human--and they are rarely fatal because the quantity of venom injected is very small. Bites may be very painful, however. The smaller male has no venom. Canon 5D Mark II, Canon 180mm macro lens, Canon Ringlite.