Marbled Orb-weaver (Araneus marmoreus)
An almost spherical abdomen painted in cream, yellow and orange and veined with dark marbling makes this one of the most striking spiders in a northern autumn. The marbled orb weaver hangs a wide wheel of silk in damp woodland edges and then vanishes into a rolled leaf at the edge of it, waiting for the signal thread to twitch.
By Dr. James WatuwaPublished January 3, 2019Updated September 13, 2026✓ Reviewed by Dr Richard J. Pearce (PhD)
In this guide
Physical description and identification
The marbled orb weaver is built around one feature: a large, almost spherical abdomen that dwarfs the rest of the animal. The ground colour is cream, yellow or bright orange, and across it runs an irregular network of dark brown, purple-black or grey veining that genuinely looks like polished marble. It is one of the most variable members of Araneus, and a single population can contain individuals that look like different species. Browse the wider orb weaver family to see how the genus fits in.
Adults
- Size: females measure about 9–20 mm in body length and look larger still when full of eggs. Males are roughly 5–9 mm, with a much smaller abdomen and longer, thinner legs.
- Colour: the abdomen ranges from white and cream through lemon yellow to deep orange, marbled with brown, black or grey. The carapace and legs are orange to light brown, the legs marked with dark rings at the ends of the segments. A widespread colour form, once treated as a separate variety pyramidatus, has a plain orange abdomen with a single large dark patch at the rear; this is the form usually called the pumpkin spider.
- Eyes: eight eyes in two rows of four on a low carapace, the middle four forming a raised square. Vision is minimal and the spider hunts entirely by vibration.
- Distinctive features: the globular abdomen with no shoulder humps, two distinct types of spine on the tibiae of the legs, and three claws on each foot for handling silk.
Eggs and egg sac
Mating takes place in late summer. In September and October the female spins a loose, fluffy egg sac of pale silk, often tucked into a curled leaf, a bark crevice or dense vegetation near the web, and lays several hundred eggs inside it. She dies within weeks, usually at the first hard frost. The sac is what carries the species through winter.
Spiderlings
The young emerge in spring and spend their first days on and around the silk of the sac before dispersing. They grow through repeated moults over the summer, building small orbs as they go, and reach maturity from midsummer onwards — earlier in the south, as late as September in the far north. The huge, conspicuous females people photograph in October are at the very end of that year-long cycle.
The web
The web is a vertical orb up to about 60 cm across, usually built low among shrubs, tall herbs and streamside vegetation. Unlike the garden spiders, this species rarely sits at the hub. Instead it builds a silk-lined retreat at the edge of the web, often a leaf rolled and stitched shut, and rests inside it holding a taut signal thread that runs to the centre of the orb. When an insect strikes, the vibration travels down that thread and the spider bursts out to wrap it. Our spider web guide explains how the spiral and radial threads are constructed.
Where the marbled orb weaver lives
Araneus marmoreus is a Holarctic species with one of the widest ranges of any orb weaver. In North America it occurs from Alaska and across Canada south to Texas, the Gulf states and Florida, with the highest densities in the north and east. The same species is common across Europe, including Britain and Ireland, and extends through Russia and temperate Asia to Japan.
It is a spider of damp, structurally complex edges rather than open ground: the margins of woodland, hedgerows, tall herb vegetation, shrubs and reeds beside ponds, streams, ditches and marshes. Moisture matters, and so does having leaves to fold into a retreat. It is much less likely than the cat-faced spider or the barn spider to set up on a building.
Are marbled orb weavers venomous?
Yes, in the ordinary sense that it uses venom on insect prey. It is not dangerous to humans. The venom of Araneus species is adapted to flies, moths and small beetles and has no medically significant effect on people or pets. This spider has none of the tissue-destroying enzymes of the recluse spiders or the neurotoxin of the widow spiders, and there are no credible records of serious harm from a bite.
Can a marbled orb weaver bite?
It can, but it is one of the least likely spiders to do so. Its whole defensive repertoire is retreat: it bolts into its leaf shelter, drops from the web on a dragline, or plays dead with its legs drawn in. A bite requires the spider to be picked up and squeezed, and its short fangs often cannot break human skin at all.
Where a bite does occur, the effect is minor: a brief sting, a small red mark and perhaps some itching, all gone within a day. Wash the area with soap and water, use a cold pack if it swells, and keep it clean. Medical advice is worth seeking only if the redness spreads over subsequent days, if pus or fever develops — which indicates a skin infection rather than venom — or if you develop hives or breathing difficulty. Skip the folk remedies, and photograph the spider if you can.
Why the size is misleading: a swollen October female looks alarming but is simply full of eggs. Fang length does not scale with abdomen size, and this spider's bite remains trivial regardless of how large she appears.
Ecological importance and behaviour of the marbled orb weaver
The marbled orb weaver is an ambush predator that lets the web do the work. Sitting out of sight in its retreat costs almost nothing and keeps the spider hidden from birds, while the signal thread reports every impact on the orb. Prey is mostly small flying insects: midges, mosquitoes, craneflies, small moths, flies, leafhoppers and beetles. Because the webs are concentrated along watercourses, the species takes large numbers of emerging aquatic insects and forms a real link between water and land food webs.
Natural predators: spider-hunting wasps are the most important. Blue mud daubers, organ-pipe mud daubers, the white-trimmed black wasp and several pompilid spider wasps paralyse orb weavers and seal them into nest cells as living food for their larvae. Birds, especially warblers and chickadees working streamside vegetation, take adults and juveniles, and parasitoid wasps attack the egg sacs.
Prey–predator dynamics: by removing biting flies and midges in exactly the habitats where they emerge, a dense population of these spiders has a measurable local effect. They in turn are an important autumn food source for insectivorous birds fattening for migration.
Courtship and mating: mature males abandon web-building and search for females in late summer, approaching along a mating thread and stroking the female's legs and body with the front pair before mating. A male may mate with more than one female and does not usually survive long afterwards; the female lives on for several more weeks to build her egg sac.
Relationship with people: harmless, seasonal and worth leaving in place. Nothing needs to be done about a marbled orb weaver except to admire it, since the adults are dead by late autumn in any case.
Similar spiders and how to tell them apart
| Spider | How it differs from the marbled orb weaver |
|---|---|
| Cross orb weaver (Araneus diadematus) | Similar shape and season, but the abdomen is brown or grey with a clear white cross of spots rather than orange-and-dark marbling. |
| Cat-faced spider (Araneus gemmoides) | Has two blunt horns on the front shoulders of the abdomen, which the marbled orb weaver never has, and prefers buildings in the dry West. |
| Shamrock orb weaver (Araneus trifolium) | Also globular and variable, but patterned with rows of pale dots on a plain ground and with strongly banded white-and-brown legs. |
| Giant lichen orb weaver | Larger, flatter and mottled green-grey like lichen, with a huge horizontal-leaning web usually built between trees. |
| Spotted orb weaver (Neoscona crucifera) | Hairier, rustier and duller, with an oval rather than spherical abdomen, and it takes the entire web down at dawn. |
| Barn spider (Araneus cavaticus) | Drab brown and banded, without marbling, and closely tied to barns, porches and other structures. |
Quick facts
| Also known as | Pumpkin spider (for the plain orange form with a dark rear patch) |
|---|---|
| Distribution | Holarctic: across Canada and the United States, throughout Europe including Britain, and east through Russia and temperate Asia to Japan. |
| Habitat | Damp woodland edges, hedgerows, tall herbs, shrubs and reeds beside streams, ponds, ditches and marshes. |
| Web | Vertical orb up to about 60 cm, with a silk-lined leaf retreat at the edge connected to the hub by a signal thread. |
| Diet | Midges, mosquitoes, craneflies, moths, flies, leafhoppers and small beetles. |
| Eggs | Several hundred, laid in a fluffy pale silk sac in September or October; the spiderlings emerge the following spring. |
| Lifespan | About one year, with a single generation annually. Adults do not survive the winter. |
| Predators | Mud daubers, spider wasps and other spider-hunting wasps, birds and egg-sac parasitoids. |
| IUCN status | Not evaluated; widespread and common throughout its enormous range. |
Did you know?
- Araneus marmoreus was named by Carl Clerck in 1757, in the first work of zoological nomenclature ever published — the book predates Linnaeus's tenth edition and its spider names are still valid today.
- The pumpkin spider form is so different from the marbled form that it was long treated as a separate variety, but both hatch from the same egg sacs.
- The leaf retreat is engineered, not found: the spider draws the edges of a living leaf together with silk and stitches it into a tube it can turn around inside.
- Because it sits out of sight, the easiest way to find one is to look for the empty hub of a fresh orb web and then follow the single taut thread leading off to one side.
- Its enormous Holarctic range means the same species can be photographed in a Finnish bog, an Ontario streamside thicket and a Japanese hedgerow.
In summary, the marbled orb weaver is a harmless, beautifully patterned, strictly seasonal spider that earns its place along every damp woodland edge by removing midges and mosquitoes at the source.
Frequently asked questions about the marbled orb-weaver
How do you identify a marbled orb weaver?
Look for a large, almost spherical abdomen in cream, yellow or orange, veined with dark brown, grey or black marbling, on an orange to light-brown carapace and legs with dark rings at the ends of the segments. Some individuals are plain orange with a single dark patch at the rear.
How big do marbled orb weavers get?
Adult females measure about 9 to 20 millimetres in body length, roughly a third to three quarters of an inch, and appear much larger when swollen with eggs in autumn. Males are considerably smaller at about 5 to 9 millimetres, with longer, thinner legs and a small abdomen.
Are marbled orb weavers venomous to humans?
They have venom for subduing insects, but it is not medically significant to people or pets. Bites are very rare, happen only if the spider is handled roughly, and produce nothing more than a brief sting and a small red mark that fades within a day.
Why is it called the pumpkin spider?
One common colour form has a plain bright orange abdomen with a single dark patch at the back, which looks remarkably like a small pumpkin. It appears at its largest in September and October, so the name has stuck. It is the same species as the marbled form.
How does a marbled orb weaver catch its prey?
It builds a vertical orb web and then hides in a silk-lined leaf retreat at the edge, holding a taut signal thread that runs to the hub. When an insect hits the web, the vibration travels down the thread and the spider rushes out to wrap and bite it.
When do marbled orb weaver spiderlings hatch?
The female lays several hundred eggs in a fluffy silk sac in September or October, then dies at the first hard frost. The sac overwinters, and the spiderlings emerge in spring. They stay on the silk of the sac for a few days before dispersing and building their own small webs.
What eats marbled orb weaver spiders?
Spider-hunting wasps are the main threat, including blue and organ-pipe mud daubers, the white-trimmed black wasp and various spider wasps, all of which paralyse spiders to feed their larvae. Birds take adults and juveniles from streamside vegetation, and parasitoids attack the egg sacs.
Where are marbled orb weavers found?
Across the northern hemisphere. In North America they range from Alaska and Canada south to Texas and Florida, and the same species occurs throughout Europe, including Britain, and east across Russia to Japan. They prefer damp woodland edges and vegetation near water.
Do marbled orb weavers come into houses?
Rarely. They are tied to damp vegetation with leaves they can fold into a retreat, so they are far less likely to appear on buildings than barn spiders or cat-faced spiders. An occasional wandering male may be found on a wall in late summer while searching for a mate.
How long do marbled orb weavers live?
About one year, with a single generation each season. Spiderlings emerge in spring, mature from midsummer, and the females live until the first hard frosts of autumn after producing their egg sac. No adult survives the winter; only the eggs do.
References
- World Spider Catalog (2026). Araneus marmoreus Clerck, 1757. Natural History Museum Bern. wsc.nmbe.ch/spec-data/9602/taxon
