Joro Spider (Trichonephila clavata) - Identification, Range & Medical Data

Summary

A large, brightly colored orb weaver native to East Asia that was first documented in north Georgia in 2014. Joro spiders have since spread across much of the southeastern United States and are projected to continue expanding because of their unusual cold tolerance for a tropical-origin spider.

Quick answers

Is Joro Spider dangerous to humans?: No. Current evidence does not link joro spider bites to serious medical outcomes in healthy adults.
How big is an adult joro spider?: Adult female body length is 17–25 mm; males are 7–10 mm. Leg span reaches 60–100 mm.
Where does Joro Spider live?: Open spaces between trees, power lines, and structures - porches, fence lines, gardens. Tolerates urban environments well. Established U.S. populations occur in 8 states.
What does Joro Spider eat and when is it active?: Flying insects including mosquitoes, flies, brown marmorated stink bugs, and bees. Adults active August–November in the southeastern U.S. Diurnal on the web.

Identification

Female body 17–25 mm with leg span up to 4 inches (100 mm)
Bright yellow body with blue-gray bands; underside red and black
Legs banded yellow and black
Builds massive golden orb webs in open spaces, often head-high
Males much smaller, brown, and inconspicuous

Morphometrics

Measurement	Female	Male
Body length	17–25 mm	7–10 mm
Leg span	60–100 mm	-
Lifespan	1–1 years	-

Trait	Value
Web type	Large, golden-tinted three-dimensional orb web, often 1–3 meters across, frequently spanning gaps between trees and structures.
Eye arrangement	Eight eyes in two rows of four.
Eggs per sac	400–1500
Egg sacs per year	1–1

Geographic range

Native range: East Asia (Japan, Korea, Taiwan, China). Introduced to north Georgia, USA, first documented in 2014.

U.S. states with established populations: Alabama, Georgia, Maryland, North Carolina, South Carolina, Tennessee, Virginia, West Virginia.

State pages covering Joro Spider

Alabama Georgia Maryland North Carolina South Carolina Tennessee Virginia West Virginia

Habitat & behavior

Habitat: Open spaces between trees, power lines, and structures - porches, fence lines, gardens. Tolerates urban environments well.

Activity: Adults active August–November in the southeastern U.S. Diurnal on the web.

Diet: Flying insects including mosquitoes, flies, brown marmorated stink bugs, and bees.

Venom & medical significance

Venom property	Value
Type	Non-medically significant
LD₅₀	Not established
Note	Bites are extremely rare; venom is not considered dangerous to humans or pets.

Bite symptoms & first aid

Symptoms

Bites are extremely rare; fangs typically too small to penetrate human skin
If a bite occurs, local irritation only

Commonly confused with

Golden silk orb weaver (Trichonephila clavipes)
Yellow garden spider (Argiope aurantia)
Banana spider (regional name disambiguation)

Key facts

Joro spiders have spread an estimated 110,000 km² across the southeastern U.S. between 2014 and 2022. [1]
Unlike most invasive arthropods, Joros are predators of brown marmorated stink bugs - an agricultural pest also introduced from Asia. [2]

Sources

[1]Davis & Frick (2022). Physiological evaluation of newly invasive jorō spiders - Physiological Entomology. Accessed 2026-06-14.
[2]Joro Spider: A New Invasive Species in Georgia - University of Georgia Cooperative Extension. Accessed 2026-06-14.