Latrodectus hesperus, the Western Black Widow spider (or Western Widow), is a venomous spider species found in western regions of North America. Female black widows have potent venom composed of neurotoxins. Fatalities usually only happen with children and the elderly, however medical treatment may be required for others as well. The male black widow is harmless to humans. Arachnids molt regularly to grow, often becoming reclusive and fasting for long periods prior to a molt. Credit to 'Macropod'.