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Spiny Orb-Weaver Spider on Live Oak in Florida: Beneficial and Harmless

A photo shows a colorful spider on a live oak in Palm Beach Gardens, Florida. Identified with help from a Florida entomologist.

Spiny orb-weaver spider

Spiny orb-weaver spider on live oak

Identification: Spiny Orb-Weaver (Gasteracantha cancriformis)

Appearance: White abdomen with black spots, large red spines on margins
Size: Females 5–10 mm long, 10–14 mm wide
Web: Contains silk tufts (may deter birds)

Beneficial Role

These spiders prey on small pest insects in crops and suburban areas, helping control overpopulations. They are not dangerous and rarely enter homes unless carried in on potted plants.

Recommendation

Do not kill. They are beneficial predators. For more information, see University of Florida extension page.

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