Last checked November 3, 2026 against official sources.
This page lists 2 spiders: all from The Poison Control Center at Children's Hospital of Philadelphia's Spider Bites. 2 are venomous by official accounts.
Not every species: no complete official list of Delaware spiders exists, so this page covers the ones state and Extension sources name. How lists are built.
Official sources single out these spiders in Delaware, in their own words:
Venomous to humans. “The venom contains a toxin that affects the nervous system.” The Poison Control Center at Children's Hospital of Philadelphia
Venomous. “The venom contains chemicals that cause severe tissue damage.” The Poison Control Center at Children's Hospital of Philadelphia
Venomous species first, then A to Z. Do not handle them.
Venom: “…only two in the United States are considered venomous to humans, and even these spiders rarely bother humans unless they are provoked. They are the Black Widow and the Brown Recluse.” (The Poison Control Center at Children's Hospital of Philadelphia)
Venom: “…only two in the United States are considered venomous to humans, and even these spiders rarely bother humans unless they are provoked. They are the Black Widow and the Brown Recluse.” (The Poison Control Center at Children's Hospital of Philadelphia)
Records of spiders in Delaware peak in June to September. They show when people record spiders, not how many there are (about month bars).
Call 911 or Poison Help at 1-800-222-1222 right away. Poison Help connects you to your local poison center, any time of day.
Official advice from The Poison Control Center at Children's Hospital of Philadelphia:
Invasive aquatic species: report to the DNREC Division of Fish and Wildlife by phone, email or the online Invasive Fish Tracker. Invasive terrestrial species: Wildlife Section, 302-739-9912. Sick or dead wildlife (five or more at one place): 302-735-3600 ext. 2. Wildlife damage biologist: 302-735-8683. DNREC
No official source places the brown recluse in Delaware. A UD Cooperative Extension entomologist (2011) names the black widow as the only poisonous spider found in Delaware, and the regional poison center says none are thought to live in Pennsylvania or farther north. The Poison Control Center at Children's Hospital of Philadelphia
“…no Brown Recluse spiders are thought to live in Pennsylvania or more northern states.”
Yes. A University of Delaware Cooperative Extension entomologist (UDaily, 2011) says the black widow is the only poisonous spider found in Delaware. The regional poison center names it as one of two venomous US spiders. University of Delaware (UDaily news office), quoting Brian Kunkel, entomologist with University of Delaware Cooperative Extension
“Only one poisonous spider is found in Delaware, the black widow.”
The species list comes from Spider Bites (Poison Control Center at Children's Hospital of Philadelphia, which serves Delaware) (The Poison Control Center at Children's Hospital of Philadelphia (serves Delaware), no date on page; checked 2026-11-03).
Venom labels come only from official sources and link to them; "Not stated" never means harmless. How labels work.
“…only two in the United States are considered venomous to humans, and even these spiders rarely bother humans unless they are provoked. They are the Black Widow and the Brown Recluse.”
“The venom contains a toxin that affects the nervous system.”
“The venom contains chemicals that cause severe tissue damage.”
“If you think you or your child has been bitten by a venomous spider, immediately contact the Poison Control Center at 1-800-222-1222 or your doctor.”
“…no Brown Recluse spiders are thought to live in Pennsylvania or more northern states.”
“It is also important to keep an eye out for invasive terrestrial species. They should be reported to the Wildlife Section, at 302-739-9912.”
“Only one poisonous spider is found in Delaware, the black widow.”
