Indiana DNR: the black widow and brown recluse are the only two Indiana spiders capable of serious injury to humans; neither is aggressive and bites are rare.
Indiana Department of Natural Resources, Division of Entomology & Plant Pathology: “Only two species found in Indiana are capable of inflicting serious injury to humans. While both the brown recluse and black widow spiders are known as venomous, neither is aggressive. Bites from them are quite rare.” Source
Venom: “While both the brown recluse and black widow spiders are known as venomous, neither is aggressive.” (Indiana Department of Natural Resources, Division of Entomology & Plant Pathology)
Habitat: Black widow spiders live in undisturbed locations and are rarely found in homes. (Indiana Department of Natural Resources, Division of Entomology & Plant Pathology)
Official presence. 15 states where a state list or official source names it. Gray means no official record in our data, not that it is absent.
Native or listed
Nonnative or not established
No official record in our data
Observation records. Open-licence records on GBIF for the three US black widows (Latrodectus mactans, L. variolus and L. hesperus) in 44 states. Records are sightings people shared, not confirmation that a population lives there.
Chocolate brown and never has red on the belly; slightly smaller than a mature western black widow (about 3/8 in body length); egg sac looks like a cotton ball with indistinct margins. Caution: UC IPM says a black widow's hourglass can be almost imperceptible or, rarely, completely absent, so a lack of red alone does not rule out a black widow.
No red hourglass and not pure black; looks purplish-brown in bright light, and larger ones have a light T-shaped mark on the abdomen. Caution: a black widow's hourglass can rarely be almost or completely absent (UC IPM), so a lack of red alone does not rule out a black widow.
Usually a mottled mix of tan, brown and gray, with a lengthwise stripe and diagonal side stripes; colour varies from almost white to almost black, and very dark ones are flat black rather than shiny black. Mature females are smaller than mature female western black widows (about 3/8 in body length). The egg sac is covered in silk bumps, like a very large pollen grain; UC IPM calls the egg sac a much surer way to confirm a brown widow. Caution: brown widows also have a red hourglass on the underside (UF/IFAS), and a mature brown widow looks very similar to an immature western black widow (UC IPM).
Penn State Extension: the female common house spider is 5 to 6 mm long with a yellowish-brown carapace and a dirty-white to brown abdomen with gray chevrons; its legs are yellow with darker rings at the end of each segment.
Blacklegged tick nymphs are most active in spring and summer, adults in fall and early spring, and adults any winter day above freezing. Indiana Department of Health
Spiders in Indiana. Indiana Department of Natural Resources, Division of Entomology & Plant Pathology. dateModified 2026-03-09; checked November 3, 2026.Quoted passages (3)
“Only two species found in Indiana are capable of inflicting serious injury to humans. While both the brown recluse and black widow spiders are known as venomous, neither is aggressive. Bites from them are quite rare.”
“While both the brown recluse and black widow spiders are known as venomous, neither is aggressive.”
“Brown recluse are often found in barns, sheds or other dry places.”
Spiders (E-72-W). Purdue University Cooperative Extension Service, Department of Entomology. November 2017; checked November 3, 2026.Quoted passages (1)
“The only spiders found in Indiana capable of inflicting serious injury to humans are the black widow and the brown recluse or "fiddleback" spider. … The poison of the black widow affects the nervous system of humans.”
Black Bear. Indiana Department of Natural Resources, Division of Fish & Wildlife. dateModified 2026-04-01; checked November 3, 2026.Quoted passages (1)
“Enjoy it from a distance. … Never attempt to feed or attract bears. Report bear sightings to the Indiana Division of Fish & Wildlife”
Ixodes scapularis (Blacklegged tick). Indiana Department of Health. Page Last Reviewed/Updated: March 2025; checked November 3, 2026.Quoted passages (1)
“In Indiana, nymphs are most active during spring and summer and adults are most active during the fall and early spring. However, adult ticks may be active any time winter temperatures are above freezing.”
