American Grass Spider, Funnel Weaver
Agelenopsis species
Agelenidae (Funnel Weavers), Order Araneae. Characterized by long spinnerets and sheet-like webs leading to a funnel retreat.
Physical Description
Elongated, teardrop-shaped abdomen and a distinct cephalothorax. The body is covered in fine hairs (setae) giving it a textured appearance. Notably, they possess two long, prominent spinnerets extending from the rear of the abdomen.
Size Estimate
Body length typically 10-20mm (0.4-0.8 inches). With leg span, they can reach 25-50mm. This particular specimen appears to be a sub-adult or adult based on leg-to-body proportions.
Coloration & Markings
Features two dark longitudinal stripes running down the cephalothorax (carapace) against a lighter tan or gray background. The abdomen often has a chevron-like pattern or a central band bordered by lighter spots.
Web Type
Builds a flat, non-sticky horizontal sheet web with a funnel-shaped retreat at one end. The spider stays in the funnel and rushes out when it senses vibrations from prey on the sheet.
Eye Arrangement
Eight eyes arranged in two rows that appear strongly curved (forming a distinctive pattern where the top row is pro-curved). Excellent motion detection for hunting.
Leg Characteristics
Long, slender, and bristly legs with numerous dark spines (macrosetae). Usually displays subtle dark banding or mottling. They are exceptionally fast runners.
Venom & Safety Information
Venom Information
Contains agelenotoxins, designed to paralyze insects. The venom is not considered medically significant to humans; the concentrated chemicals are being studied for neurological research.
Medical Significance
Low danger level. Bites are extremely rare due to the spider's timid nature. If a bite occurs, it typically results in redness, itching, or minor localized swelling, similar to a bee sting.
Safety Recommendations
If found indoors, they can be easily relocated using a cup and card. They pose no threat to pets or structural integrity and are best left alone to provide free pest control.
Habitat & Behavior
Habitat & Range
Found throughout North America. Common in gardens, low-lying shrubs, grass, and occasionally wandering into houses, basements, or window wells during autumn.
Behavior & Temperament
Elusive, fast-moving ambush hunters. They are non-aggressive toward humans and will almost always retreat into their funnel at the slightest vibration. Very shy and sensitive to light changes.
Diet & Prey
Primarily small insects like crickets, moths, and flies. They rely on speed to dash out and bite prey that lands on their sheet web before dragging it back into the funnel.
Seasonal Activity
Most visible in late summer and autumn when webs become large and males wander in search of mates.
Description
The Grass Spider is a staple of North American landscapes, often recognized more by its expansive dew-covered webs than the spider itself. It is a master of speed and precision, acting as a natural sentinel in gardens.
Key Features
Prominent elongated spinnerets at the rear of the abdomen and two parallel dark racing stripes on the head region.
Similar Species
Often confused with Wolf Spiders (Lycosidae), which do not have long spinnerets and do not build webs, or the Hobo Spider (Eratigena agricola), which lacks the distinct stripes on the carapace.
Life Cycle
Females lay egg sacs in crevices or under bark in late summer/fall. The spiderlings hatch in spring. Adults usually live for one season, dying after the first hard frost.
Ecological Importance
Highly beneficial for pest control, consuming large quantities of garden pests and indoor nuisance insects like gnats and flies.
Conservation Status
Common and widespread; not currently listed as a species of concern.
Interesting Facts
Despite their intricate webs, the silk is not sticky. They rely entirely on their extreme running speed to catch prey before it can fly or crawl off the silk platform.
Photography Tips
Focus on the 'racing stripes' on the head and the long spinnerets at the back. Shooting from a low angle at the entrance of the funnel web provides the best view of the spider's face.
Identified: 2026-07-08T16:19:50.300048