Cat-faced Spider, Jewel Spider
Araneus gemmous
Araneidae (Orb-Weavers), Order Araneae. Key family characteristics include strong sexual dimorphism, robust hairy bodies, eight similar-sized eyes in a compact cluster, and the ability to spin classic vertical orb webs.
Physical Description
Robust, stout-bodied spider with a distinctively wide, triangular or shield-like abdomen featuring two prominent lateral humps or tubercles that give it the common name 'cat-faced' or 'jewel' appearance. The cephalothorax is smaller, covered in fine setae, and joins a plump, bulbous abdomen.
Size Estimate
Body length ranges from 13 to 25 mm for adult females, with males being significantly smaller around 8 mm. Leg span can reach up to 40 to 50 mm.
Coloration & Markings
Variable base coloration ranging from light cream, beige, yellowish-brown, to dark orange or deep reddish-brown. The abdomen typically features a characteristic light-colored pattern resembling a cat's face, complete with dark spots representing eyes and ears.
Web Type
Constructs large, vertical orb webs made of sticky silk, often spanning several feet across. These webs are typically built in late summer and autumn around building exteriors, porch lights, gardens, and shrubbery.
Eye Arrangement
Eight eyes arranged in two distinct rows on the anterior portion of the cephalothorax, consisting of a median square flanked by lateral pairs, typical of the orb-weaver family Araneidae.
Leg Characteristics
Moderately long, thick legs covered in numerous prominent spines and distinct dark banding patterns. Legs are often held in a characteristic sprawling posture when resting on the web or retreat.
Venom & Safety Information
Venom Information
Neurotoxic venom tailored specifically for immobilizing insect prey. It has low potency regarding vertebrates and humans.
Medical Significance
Harmless to humans. A bite may cause minor, localized pain, slight swelling, or redness similar to a mild bee sting, but it is not medically significant.
Safety Recommendations
No special safety measures required. If relocation is necessary, gently guide the spider into a container using a piece of cardstock and release it outdoors in a garden or shrub.
Habitat & Behavior
Habitat & Range
Found primarily across western North America, stretching from British Columbia down through California and eastward into the Rocky Mountain states. Prefers gardens, exterior walls of homes, orchards, and woodland edges.
Behavior & Temperament
Docile and non-aggressive. Spiders are nocturnal web-builders, often spending daylight hours hiding in a nearby retreat or clinging to the edge of the web, and moving to the hub at dusk.
Diet & Prey
Generalist predator feeding on flying insects including moths, flies, mosquitoes, beetles, and wasps intercepted by the orb web.
Seasonal Activity
Most active and noticeable in late summer and autumn when females reach maximum size, lay eggs, and complete their annual life cycle.
Description
The Cat-faced Spider is a familiar and fascinating autumn visitor in western North America. Recognized instantly by the prominent bumps on its abdomen that resemble feline ears, this orb-weaver spends its nights at the center of a finely spun wheel of silk waiting for flying prey. Despite their somewhat menacing appearance, they are completely harmless pest controllers.
Key Features
Two prominent lateral bumps on the upper abdomen forming a cat-face or skull-like pattern, hairy robust body, large vertical orb web, and distinct leg spination.
Similar Species
Araneus diadematus (European Garden Spider), which features a cross pattern on the abdomen rather than lateral bumps, and Neoscona species, which tend to have more rounded, less angular abdomens.
Life Cycle
Females construct brownish silk egg sacs in sheltered cracks or crevices in autumn, containing hundreds of eggs. Spiderlings hatch in spring, disperse via ballooning, and mature by late summer.
Ecological Importance
Serves as an effective biological control agent by consuming large quantities of flying agricultural and household insect pests.
Conservation Status
Not evaluated by the IUCN, but populations are secure, widespread, and highly adaptable to human-modified environments.
Interesting Facts
Cat-faced spiders often consume and rebuild their entire orb web every single day to maintain the stickiness of the silk and recycle proteins.
Photography Tips
Photograph from the side or slightly above to capture the unique abdominal tubercles. Use macro lenses with a fast shutter speed, and photograph at dusk or night when the spider is active at the web center.
Identified: 2026-09-18T22:48:01.917753