Marbled Orb Weaver Male vs Female: Discover the Key Differences

The marbled orbweaver spider is a fascinating creature, known for its vibrant colors and unique patterns. These spiders are commonly found in various parts of the eastern United States and display a range of colors and markings on their bodies, primarily on their large abdomens link. The most critical aspect, however, when discussing marbled orbweavers, is the key differences between males and females, which we will explore in this article.

Differences in size, color, and markings are important aspects of marbled orb weaver spiders that make identification a bit easier. Adult female marbled orbweavers tend to be larger, measuring 9 to 20 millimeters in length, while males sport more compact sizes. The abdomens of females usually feature colors such as orange, brown, purple, and even white, with spots of various shades, including pale yellow link. Males, on the other hand, have more subtle color variations compared to their female counterparts.

Understanding the distinctions between male and female marbled orbweaver spiders is crucial for enthusiasts and researchers alike. This knowledge allows for a more comprehensive analysis of these captivating creatures, their mating behaviors, and their overall contributions to the ecosystem.

Marbled Orb Weaver: Overview

Scientific Classification

The Marbled Orb Weaver (Araneus marmoreus) belongs to the following classification:

  • Kingdom: Animalia
  • Phylum: Arthropoda
  • Class: Arachnida
  • Order: Araneae
  • Family: Araneidae
  • Genus: Araneus
  • Species: A. marmoreus

General Appearance

Adult female marbled orbweavers have large abdomens, measuring between 9 to 20 millimeters in length. Their color varies from mostly orange to white, with brown to purple markings and spots of pale yellow. The cephalothorax is yellow to burnt-orange, with a central dark line and dark lines down either side (source).

Range and Distribution

Marbled orbweavers have a wide distribution, inhabiting various regions across North America and Europe. In North America, they can be found in areas such as Alaska, Canada, North Dakota, Oregon, and Texas (source).

Habitat

These spiders are known to live in a variety of habitats, including:

  • Forests
  • Gardens
  • Grasslands
  • Wetlands

Marbled orbweavers build their webs in shrubs, trees, and other vegetation, typically near the ground (source).

Physical Characteristics

Coloration and Markings

  • Marbled orb weavers have wide color variation, ranging from:
    • Orange
    • Yellow
    • Red
    • White
    • Pale yellow
    • Brown
    • Black (sometimes with purple markings)
  • Common markings include mottled patterns on their carapaces and cephalothoraxes.
  • Legs often have striped patterns.

Size and Shape

  • Size: Females are larger, measuring 9-18 mm, while males are smaller at 6-9 mm.
  • Shape: Both genders have a rounded cephalothorax and an oval-shaped abdomen.

Sexual Dimorphism

  • Females are larger and have more vibrant colors.
  • Males have smaller, narrower abdomens and longer tibia on their first pair of legs.
Feature Males Females
Size 6-9 mm 9-18 mm
Color Less vibrant, darker colors Vibrant colors with noticeable patterns
Abdomen Shape Smaller and narrower Larger with more rounded shape
Leg Characteristics Longer tibia on the first pair of legs Tibia of similar length on all legs

Lifecycle and Reproduction

Mating and Pheromones

Male marbled orbweaver spiders detect the presence of females by sensing their pheromones. This chemical signal helps males locate potential mates. During mating, the male transfers his sperm to the female via structures called pedipalps.

Egg Sacs and Spiderlings

After mating, female marbled orbweavers create silk egg sacs to protect their eggs. These sacs:

  • Are typically found in hidden locations
  • Contain around 400 to 1000 eggs
  • Hatch in spring, resulting in numerous spiderlings

Lifespan

The lifespan of marbled orbweaver spiders differs between the genders:

  • Males: Shorter lifespan, typically die after mating
  • Females: Longer lifespan, can live up to one year
Gender Lifespan
Male Short
Female Up to 1yr

Seasonal changes affect marbled orbweaver spiders:

  • Spring: Spiderlings hatch and grow throughout the season
  • July: Mating season begins
  • Fall: Females lay eggs in sacs, adult spiders typically die

Features of marbled orbweaver spiders:

  • Vibrant colors and patterns
  • Males smaller than females
  • Orb-shaped webs

Characteristics of marbled orbweaver spiders:

  • Quick web builders
  • Predatory insects
  • Good at camouflage

Web and Feeding Habits

Types of Webs

Marbled orb weaver spiders are known for spinning distinctive orb webs. These webs typically have a circular shape and are constructed between sturdy supports, such as doorways, windows, or plant stems1. The webs are made from silk, which is used to create a sturdy structure that efficiently captures prey.

Features of orb webs:

  • Circular in shape
  • Sturdy structure
  • Built between robust supports

Prey and Hunting Techniques

Marbled orb weavers primarily feed on various insects that happen to fly into their webs. Once the prey is trapped, the spider quickly incapacitates it by injecting venom2. Some examples of prey include:

  • Flies
  • Mosquitoes
  • Moths

Signal Thread

One crucial aspect of the marbled orb weaver’s web is the signal thread, which plays a vital role in detecting trapped prey. The signal thread is a single silk strand that extends from the center of the web to the spider’s silken retreat3. When an insect becomes caught in the web, the vibrations travel along the signal thread to alert the spider, which then investigates the disturbance.

Characteristics of the signal thread:

  • Single silk strand
  • Connects the web center to the spider’s retreat
  • Transmits vibrations from trapped prey

Interaction with Predators and Other Species

Predators and Venom

Marbled orb-weaver spiders, also known as pumpkin spiders, are part of the orb-weaving spider family. They can be found across North America, from South Carolina to Oregon, and in a variety of habitats, including wooded settings and the banks of streams. These spiders have adapted various defense mechanisms to protect themselves from predators.

  • Venom: Like other orb-weaving spiders, marbled orbweavers have venom, which they use to immobilize and kill their prey, such as moths and other small insects. However, their venom is not considered dangerous to humans.
  • Habitat: Marbled orbweavers often build their webs in moist, forested areas near streams, which provides them with a natural shelter from predators such as birds and larger insects.

Relationship with Wasps

Several wasp species are known to prey on marbled orbweavers and other orb-weaving spiders:

  • Blue mud daubers: These wasps specifically target orb-weaving spiders, paralyzing them with their venom and carrying them back to their nests as food for their larvae.
  • Spider wasps: A variety of spider wasps hunt orb-weaving spiders, including the white-trimmed black wasp and organ pipe mud daubers.

The interaction between marbled orbweavers and wasps can be seen as an example of the complex predator-prey relationships that exist in nature. The wasps benefit by using the orbweavers as a food source, while the orbweavers serve as a natural form of population control for the wasps.

Comparison Table: Marbled Orbweavers vs. Other Orb-Weaving Spiders

Feature Marbled Orbweaver Argiope Garden Spiders European Garden Spider
Adult Female Size 9-20 mm in length with large, colorful abdomens 14-24 mm in length Similar size as Marbled Orbweaver
Geographic Range Across North America, particularly in moist, wooded settings North America and Europe Europe and North America
Habitat Found near forest streams, building webs in wooded areas Gardens and grasslands Gardens and grasslands
Predators Birds, larger insects, blue mud daubers, spider wasps Birds, wasps Birds, wasps

Marbled orbweavers share several features with Argiope garden spiders and European garden spiders. All three species are orb-weaving spiders found in North America and have similar sizes. However, marbled orbweavers are more often found in moist, wooded habitats, while Argiope and European garden spiders are more commonly found in gardens and grasslands. All three species have predators that include birds and various wasp species.

Conservation and Human Interactions

Marbled orb-weavers are part of the Araneomorphae, a classification of spiders within the Chelicerata1. These spiders are typically found in wooded settings, near banks of streams, or among tall weeds2. Their distribution spans across the eastern United States3.

Humans may occasionally encounter marbled orbweavers in their natural habitats. However, the species is generally considered harmless to humans. Here are some distinguishing features of marbled orbweavers:

  • Mostly orange with brown to purple markings
  • Spots of pale yellow on the abdomen
  • Yellow to burnt-orange cephalothorax with a central dark line

While the conservation status of this species is not specified, it’s essential to protect natural habitats, such as wooded settings, stream banks, and tall weeds. These environments support not only marbled orbweavers but also a diverse set of species, including other orbweavers and various forms of wildlife4.

Protecting these natural habitats can be most effectively achieved by:

  • Limiting overdevelopment in rural and wooded areas
  • Maintaining and restoring natural vegetation in yards and landscapes
  • Reducing the use of pesticides that might harm orbweavers and other beneficial organisms

Footnotes

  1. Fall is spider season as orb-weavers spin bigger webs 2

  2. Marbled Orbweaver Spider 2

  3. Basilica Orbweaver Spider 2

  4. https://www.fws.gov/story/2022-04/north-american-model-wildlife-conservation-wildlife-everyone

Reader Emails

Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.

Letter 1 – Marbled Orbweaver

 

gorgeous spider
Location: Eastern Long Island, NY
November 1, 2010 1:26 pm
My teacher found a spider with a reddish coral colored body (cephalothorax), red and white/clear striped legs, and a black and yellow abdomen that looks like a Rorschach test. The spider was about .5 inch long.
Signature: spider nerd

Marbled Orbweaver

Dear spider nerd,
Sometimes we go back a ways through unanswered mail to find an interesting letter to post, and today we happened upon your lovely image of a highly variable Marbled Orbweaver,
Araneus marmoreus.  This is only one possible color combination, but it is a distinctive one.  You can compare your photo to this image posted to BugGuide.

Letter 2 – Marbled Orbweaver

 

(11/3/2003)Unidentified spider
I found this spider wandering yesterday in the leaf litter in Great Falls, Maryland, about 10 miles north of Washington, DC.  It’s “dome” was about the diameter of a dime or a penny.  I’ve never seen anything like it before and my Internet search came up empty.  I’d really like to know what it is.  Thanks!
Jerry Singer

Update to orange spider question
Upon further Net research, I found a picture of the spider I sent to you at the bottom of this page. It was identified as Araneus sp.  I also found a very similar spider identified as araneus quadratus at this site. Neither site provides much info, so I would appreciate any more that you could provide.  Thanks!
Jerry

Marbled Orbweaver

Dear Jerry,
Your photo is beautiful, much nicer than the Araneus sp. image on the website you cited. Here is what I can tell you about the genus. It is a large one with approximately fifty species identified. They are orb web weavers and most species exhibit considerable variability regarding coloration and markings. If I were to venture a guess as to your species, I would say Aranea gigas conspicellata. There is an image on this site: which looks just like yours. It is an extremely variable species in size, color and markings. The full-grown female, which you photographed, measures about 3/4 inch excempting the legs. The web is a complete orb and is often a foot or more in diameter. It is nearly vertical and is usually built in shrubs or among the low branches of trees. The retreat is usually above the orb and is frequently made in a curled leaf or in a bunch of leaves. In the Northern States the spiders reach maturity in August. The egg sacs are made early in the autumn.

Ed. Note: We now believe this to be a Marbled Orb Weaver, Araneus marmoreus. It is a shy spider which hides in a retreat, only emerging when prey has been snagged in its web.

Letter 3 – Marbled Orbweaver

 

Spider in Ohio
Location: Brook Park, Ohio
November 1, 2011 6:14 pm
Just curious what type of spider this is and if it is poisonous. I remember hearing loud bright colors means deadly. True? Thanks.
Signature: DST

Marbled Orbweaver

Dear DST,
This is one of the many recognized color variations of the Marbled Orbweaver,
Araneus marmoreus.  You can see some of the other color variations on BugGuide.

Letter 4 – Marbled Orbweaver

 

Subject: Crab-spider thing
Location: Washington, D.C.
November 17, 2013 10:01 am
Hi there, we just found this spider that has a multi-colored body that almost looks like a shell. We found him today, November 17, on our front stoop in Washington, DC. He was about a centimeter long with his legs bent.
Signature: Nancy

Marbled Orbweaver
Marbled Orbweaver

Dear Nancy,
This is a Marbled Orbweaver,
Araneus marmoreus, a species with highly variable coloration and markings.  Your individual is a female.  This yellow variation is quite common and it is pictured on BugGuide.  There is also an orange variation that is commonly called a Pumpkin Spider, both for the color and the seasonal appearance in the autumn near Halloween.  Like many other Orbweavers, the Marbled Orbweaver only lives a single season, and eggs that hatch in the spring produce individuals that mature in the fall.  Since they reach maximum size at that time, they are highly visible in the autumn.  More information on the Marbled Orbweaver is available on BugGuide.    

Letter 5 – Marbled Orbweaver

 

Subject: Crazy colorful spider
Location: Roanoke, VA
September 5, 2015 11:04 am
Can you help us identify this spider? My husband found it o his truck in Roanoke, VA on Sept. 5. We live in primarily woods with some pasture. Thank you!
Signature: Suzanne

Marbled Orbweaver
Marbled Orbweaver

Dear Suzanne,
Your image represents one possible color variation of the highly variable Marbled Orbweaver,
Araneus marmoreus, and you can find a matching image posted to BugGuide.  A bright orange color variation is known as the Pumpkin Spider.

Letter 6 – Marbled Orbweaver

 

Subject: What spider is this
Location: Northeast pa
January 5, 2016 10:50 am
This spider was on the wall of my basement in northeastern Pennsylvania in summer, is it an Orbweaver?
Signature: VeronicaFox

Marbled Orbweaver
Marbled Orbweaver

Hi Veronica,
This is a yellow individual of the highly variably colored Marbled Orbweaver,
Araneus marmoreus, and you can verify our identification on BugGuide.  Bright orange Marbled Orbweavers are commonly called Pumpkin Spiders.

Letter 7 – Marbled Orbweaver and Suggestion

 

suggestion
November 10, 2009
I’m wondering if any of the other WTB addicts out there would agree with the idea that it would be cool to eliminate the bug’s name from the title of each submission, so that we can test our knowledge when we see the pic? Obviously it would be left in the body of your response.
Here’s a spider pic (because apparently I can’t submit a Q without one & because I’m not sure if this is a marbled orb weaver- it looks different than the one in my book).
Vince
Northern Indiana

Marbled Orbweaver
Marbled Orbweaver

Hi Vince,
Your suggestion does bring up some possibilities in our minds, most significantly the thought of pitching a game show to the animal planet.  Amateurs that we are, we do post a significant number of unidentified images and we rely heavily upon our readership to supply us with answers.   We are happy you needed to attach a photo as this is a color variation of the Marbled Orbweaver, Araneus marmoreus, that we do not often see.  It is well represented on BugGuide.

Authors

    by
  • Bugman

    Bugman aka Daniel Marlos has been identifying bugs since 1999. whatsthatbug.com is his passion project and it has helped millions of readers identify the bug that has been bugging them for over two decades. You can reach out to him through our Contact Page.

  • Piyushi Dhir

    Piyushi is a nature lover, blogger and traveler at heart. She lives in beautiful Canada with her family. Piyushi is an animal lover and loves to write about all creatures.

8 thoughts on “Marbled Orb Weaver Male vs Female: Discover the Key Differences”

  1. We call these “People Catchers” in my family, because their webs are so strong (and almost always right across the path/porch steps/etc) that you practically bounce backward when you walk into one. You always know fall is just around the corner when you hear the ping! snap! of People Catcher webs every time you walk outside!

    Reply
    • BugGuide data does indicate sightings in the south. Though venomous, the bite of a Marbled Orbweaver is not considered dangerous to a human and it will likely only cause localized discomfort and swelling.

      Reply
  2. We had to move the kayaks for construction so we relocated her/him to a tree. She/He went to the very top and wove another web. Seems happier in new home.

    Reply

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