Spotted Orb-Weaver, Barn Spider
Neoscona crucifera
Araneidae (Orb-Weavers), Order Araneae
Physical Description
The body is robust and typically oval to rounded in shape. The cephalothorax is somewhat smaller and covered in fine hairs, while the abdomen is large, swollen, and bulbous, designed for egg production. Females are significantly larger than males, displaying pronounced sexual dimorphism.
Size Estimate
Body length ranges from 9 to 19 mm for females and 8 to 13 mm for males, with a total leg span reaching up to 35 to 40 mm. This specimen appears to be an adult.
Coloration & Markings
Base coloration varies widely from yellowish-brown, reddish-brown, to grayish-black. The dorsal abdomen often features a distinct cross-like pattern or a series of spots and chevron markings, framed by lighter margins.
Web Type
Builds a classic, vertical, temporary orb web characterized by sticky spiral lines and a central hub. These webs are typically constructed in the evening on structures, windows, or vegetation and often taken down at dawn.
Eye Arrangement
Arranged in two horizontal rows of four eyes each on the anterior portion of the carapace, with the lateral eyes often touching or closely grouped, typical of the orb-weaver family Araneidae.
Leg Characteristics
Legs are moderately long, stout, and armed with numerous spines and distinct dark banding patterns. They are often held wide apart to maximize sensory perception of vibrations in the web.
Venom & Safety Information
Venom Information
Venom is neurotoxic to insect prey but is extremely mild and considered medically insignificant to humans. A bite rarely occurs unless the spider is severely pressed against the skin.
Medical Significance
Harmless to humans. Bites may cause localized, minor pain, redness, or slight swelling that subsides quickly without medical treatment.
Safety Recommendations
Leave undisturbed when outdoors. If found on a window or door frame, gently guide it into a container using a piece of card and relocate it to nearby garden foliage.
Habitat & Behavior
Habitat & Range
Common throughout North America, frequently found near lights, building exteriors, windows, gardens, woodland edges, and tall grasses where flying insects congregate.
Behavior & Temperament
Docile and non-aggressive. They spend daylight hours hiding near the web or resting in a retreat, becoming active at dusk to construct or repair their webs and wait for prey.
Diet & Prey
Feeds primarily on nocturnal flying insects including moths, mosquitoes, beetles, and midges trapped in the vertical orb web.
Seasonal Activity
Peak activity occurs during late summer and autumn when adults reach full size and mating occurs. Overwinters in the egg stage.
Description
The Spotted Orb-Weaver is a familiar and beneficial nocturnal architect found around human habitations. With its bulbous abdomen and intricate patterning, it is a master web-builder that serves as a natural pest controller, spinning large circular webs near lights to capture flying insects.
Key Features
Rounded, bulbous abdomen with cross or chevron markings, hairy brownish body, and construction of a large vertical orb web.
Similar Species
Neoscona domiciliorum (Red house spider) and Araneus cavaticus (Barn spider), distinguished primarily by subtle variations in dorsal abdominal patterning and coloration.
Life Cycle
Females produce silken egg sacs in autumn, attaching them to sheltered surfaces. Spiderlings hatch in spring, disperse via ballooning, and mature through successive molting cycles over a single season.
Ecological Importance
Acts as a primary biological control agent for flying insect populations around homes and gardens, contributing significantly to natural pest suppression.
Conservation Status
Secure and widespread, with stable populations facing no significant conservation threats.
Interesting Facts
These spiders frequently consume and rebuild their entire orb webs nightly to recycle silk proteins and maintain the stickiness of the capture threads.
Photography Tips
Photograph during early evening or night using a macro lens and a diffused flash to highlight the intricate patterns on the dorsal abdomen against the vertical web background.
User Notes
Found on window
Identified: 2026-08-03T16:29:09.623115