Geographic constraint
Verified Loxosceles populations occupy a well-defined range across Kansas, Oklahoma, Texas, Arkansas, Missouri, Louisiana, Mississippi, Alabama, Tennessee, Kentucky, southern Illinois, southern Indiana, southern Ohio, and parts of Georgia. Presumed 'recluse bites' outside that range are statistically almost never recluse bites.
Vetter (2005) collected fewer than ten verified Loxosceles specimens in California across a multi-year public solicitation despite thousands of presumed bite reports - illustrating the gap between perceived and actual exposure.
Differential diagnosis
MRSA, herpes zoster, pyoderma gangrenosum, diabetic ulcers, lymphomatoid papulosis, and chemical burns all produce necrotic lesions that are routinely misattributed to spider bites.
References
- [1]Causes of necrotic wounds other than Loxosceles spider bites - Vetter RS - Toxicon. Accessed June 2026.
Related in Bites and medical
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