Marbled orbweaver

Conservation Status

IUCN Red List

NNR - Unranked

NatureServe

NNR - Unranked

Minnesota

NNR - Unranked

Description

Marbled orbweaver is a medium-sized orb weaver spider. Females are much larger than males, ⅜″ to 11 ⁄16″ long and 1 ⁄16″ to ¼″ wide, with a legspan up to 17 ⁄16″. Males are about half as big, ¼″ to ⅜″ long and 1 ⁄16″ to ⅛″ wide.

Like all spiders, it has two body parts. The hardened plate (carapace) covering the front part (cephalothorax) is light brown or orange with a narrow dark stripe down the middle and on each side.

The abdomen is and rounded and smooth, with no bumps toward the rear. On the female it is large and rounded. On the male it is proportionately smaller and more elongated. The color and pattern of the abdomen is highly variable both regionally and seasonally. It has a white, yellow, orange, brownish, or pink background color. There are always highly contrasted black, gray, and white markings, at least at the front edge, that give it a marbled appearance. These markings may fade as the season progresses.

The legs are 11 ⁄16″ to 17 ⁄16″ long and spiny. Males have proportionally longer legs than females. The ends of the legs are banded with black and either clear or white. The third (femur) and fourth (patella) leg segments are often light brown or orange, the same color as the carapace. Sometimes these segments are banded.

The face is small. There are eight eyes, all of them small, in two rows.

Size

Female Body Length: ⅜″ to 11 ⁄16″

Male Body Length: ¼″ to ⅜″

Legspan: 11 ⁄16″ to 17 ⁄16″

Web

Marbled orbweavers spin a large circular web that hangs vertically. This web is called an “orb”, which gives this family of spiders its common name. The orb is typically a closed hub, 20″ to 30″ in diameter, with 15 to 35 spokes (radii) that are not sticky. The radii extend to the center of the hub. They are connected to each other by sticky threads that spiral outward from the center. The spider also makes a retreat out of silk near one edge of the orb. The retreat is connected by a signal thread to the center of the web, allowing the spider to feel vibrations of prey. The web is usually consumed and a new web constructed each evening.

Similar Species

Habitat

Shrubs, tree branches, or tall grass; woodland edges, stream banks, gardens, fences, bridges, and other human-made constructions

Ecology

Foraging

Web builder (Passive Hunter)

Prey

Flying insects

Behavior

They will drop to the ground and hide if approached.

Males are unable to capture prey larger than themselves.

Life Cycle

Several hundred orange eggs are deposited in a mass and then wrapped in silk producing a flattened spherical egg sac. The egg sac is then attached to nearby vegetation or to the spider’s retreat. Some eggs hatch in late summer or fall, others overwinter in egg sacs. Spiderlings disperse by “ballooning”. They climb a branch, blade of grass, or fencepost, and release a long thread of silk. The silk thread catches the wind or even a light breeze and the spiderling floats to a new site.

Adults are active from mid-summer to the first hard freeze in fall.

Season

Spring to the first hard freeze in fall

Distribution

Sources

7, 24, 30, 82, 83.

Araneus marmoreus Clerck, 1757 in Bánki, O., Roskov, Y., Döring, M., Ower, G., Hernández Robles, D. R., Plata Corredor, C. A., Stjernegaard Jeppesen, T., Örn, A., Pape, T., Hobern, D., Garnett, S., Little, H., DeWalt, R. E., Miller, J., Orrell, T., Aalbu, R., Abbott, J., Abreu, C., Acero P, A., et al. (2026). Catalogue of Life (2026-07-17 XR). Catalogue of Life Foundation, Amsterdam, Netherlands. https://doi.org/10.48580/dgykv