Brown Recluse (Loxosceles reclusa)

Because the brown recluse cannot live in temperatures below 40°F, Michigan is not high on its list of vacation hotspots. In fact, the brown recluse is extremely rare in Michigan, having been documented here only once. In this case the spiders were found in a heated building and were probably introduced in materials shipped from the southern United States.

Soft-bodied, yellowish-tan to dark brown, the brown recluse is about ¼ to ½-inch long and have long, delicate gray to dark brown legs covered with short, dark hairs. They have 3 pairs of eyes arranged in a semicircle on the front of the head. The recluse also has a violin-shaped marking behind the eyes. The neck of the violin points away from the head toward the abdomen.

Brown recluse spiders are most active at night and prefer dark, undisturbed areas. Like the black widow, the brown recluse is not aggressive but will bite if disturbed. Bites are rarely fatal but do require immediate attention by a physician.