Necrotic Araneism. A Review of the Loxosceles Genus. I. General Aspects, Distribution and Venom Composition

The “violin” spider, Loxosceles sp is implicated in causing necrotic skin lesions, secondary complications, and in some instances, even considered life-threatening. Fatalities are rare but are much more common in children, the ill, and the elderly. Diagnosis is often made by examining the lesion after the bite and rarely is a spider identified at the time of the attack. The “fiddle back” spider is distributed extensively in Mexico, with the majority of the species living in the Northern states. These spiders have a preference of hiding in closets, boxes, waste material, under rocks and in crevices and are considered “synanthropic”.