Brown recluse

How to recognise it

These are the features that identify a brown recluse. Each one is described in words so the identification works without the diagram.

1. Six eyes arranged in three pairs forming a semicircle, rather than the eight eyes of nearly all other spiders. This requires magnification and is the only reliable diagnostic feature.
2. The legs are uniformly coloured with no bands, stripes, or spines — a banded or spiny-legged spider is not a recluse.
3. The body is uniform tan to dark brown, 6 to 12 mm, with a leg span around 25 mm.
4. A darker violin-shaped mark on the cephalothorax with the neck pointing backward is often present, but many harmless spiders have similar markings and some recluses show it faintly. Do not identify on this feature alone.

What it leaves behind

• Irregular, wispy sheet webbing in undisturbed storage, in boxes, and behind stored items — recluses do not build orb webs.
• Shed skins in undisturbed corners of basements, attics, and cupboards.

Why an infestation persists

Recluses are genuinely reclusive and bites are uncommon relative to how often they are blamed. Most bites occur when a spider is pressed against skin — in clothing, bedding, or gloves that have been stored undisturbed. Bite outcomes vary widely and most heal without intervention, but a minority produce a necrotic lesion. Many wounds diagnosed as recluse bites are later found to be other conditions, including infections, which is one reason a suspected bite belongs with a medical professional rather than a website.

Where it occurs

A well-defined range across the central and southern Midwest and mid-South — broadly Kansas, Oklahoma, Texas, Arkansas, Louisiana, Missouri, Iowa, Nebraska, Illinois, Indiana, Kentucky, Tennessee, Mississippi, Alabama, and Georgia. Reports far outside this range are very frequently misidentified.

Where to look for it

• [object Object]
• Behind and beneath furniture pushed against a wall, and inside a wardrobe that is rarely opened.
• Clothing, shoes, and gloves left on the floor or stored in a garage, attic, or basement.
• Between a mattress and a wall, and under a bed used for storage.
• Wall voids, crawl spaces, and behind loose skirting.
• Under a torch at night, when the eyes of most spiders reflect — a recluse's six eyes do not produce the same shine as the eight-eyed spiders it is confused with.

When you see it, and why

Encounters rise in spring and again in autumn as spiders move, and in summer when people disturb long-untouched storage during clear-outs. That last one is the recurring pattern in reported bites: the spider is pressed against skin inside clothing, bedding, or a glove that had been stored undisturbed. Seasonality matters less here than the act of disturbing storage.

What getting the identification wrong costs you

This is the most over-reported spider in North America, and the direction of error is almost always the same: a harmless spider identified as a recluse. Wolf spiders, cellar spiders, and various funnel weavers are all routinely misidentified. The violin marking is not diagnostic — many harmless spiders carry a similar mark and some recluses show it faintly. Six eyes in three pairs is the deciding feature and needs magnification. Outside the central and southern Midwest and mid-South, the odds are strongly against it.

What a professional actually does

The honest answer is that identification is the service worth buying here, and your county extension service will frequently do it at no cost and better than a sales visit would. If a specimen is confirmed and the property is within the established range, the useful work is decluttering and sealing storage areas — which is largely labour you can supply. Be sceptical of any quote issued for a recluse infestation without a confirmed specimen.