Araneus Orb Weavers are a fascinating group of spiders known for their impressive webs and intriguing appearances. These arachnids are part of the Araneidae family and can be found in various environments around the world. Their unique features and intriguing behavior make them an excellent topic for exploration.
One of the most significant characteristics of Araneus Orb Weavers is their distinctive web-building abilities. Their webs are typically large, intricate, and efficient at catching prey. These spiders are also known for their diverse appearances, with some species displaying vibrant colors and intricate patterns.
Some noteworthy examples of Araneus Orb Weavers include the Marbled Orbweaver Spider and the Cross Orbweaver Spider. In the context of their environment, these creatures play a crucial role in controlling insect populations and providing a valuable source of food for other animals.
Araneus Orb Weaver Identification
Physical Characteristics
Araneus orb weaver spiders are known for their distinctive orb-shaped webs. Some key features of these spiders include:
- Eight legs
- Two main body parts: cephalothorax and abdomen
- Spinnerets for producing silk
Size
Araneus orb weavers vary in size, but generally speaking:
- Females: 9 to 20 millimeters in length
- Males: smaller than females
Coloration
These spiders can have diverse color patterns, with some examples being:
- Orange abdomens with brown to purple markings and pale yellow spots, as seen in marbled orbweavers
- Yellow to brown background color with wavy or scalloped lines, like the cross orbweaver
Sexual Dimorphism
Males and females of the Araneus orb weaver species show differences in size, color, and reproductive structures. For instance:
- Males: smaller than females, often with different color patterns
- Females: larger, with distinctive epigyne (the female reproductive structure)
Comparison Table:
| Feature | Male | Female |
|---|---|---|
| Size | Smaller | Larger (9 to 20 mm) |
| Color Patterns | May differ from females | Unique patterns for species |
| Reproductive Organs | Palp (modified leg for mating) | Epigyne (female structure) |
Remember, when identifying Araneus orb weaver spiders, it’s helpful to consider multiple factors like size, coloration, and sexual characteristics.
Classification and Species
Taxonomy
Araneus Orb Weaver spiders belong to the family Araneidae and the genus Araneus. They are classified under the kingdom Animalia, phylum Arthropoda, subphylum Chelicerata, class Arachnida, order Araneae, and infraorder Araneomorphae1.
Common Araneus Species
There are several different Araneus species, with some commonly known ones listed below:
- Araneus marmoreus: Also known as the Marbled Orb Weaver.
- Araneus quadratus: Common in Europe2.
- Araneus saevus: Found in North America3.
- Neoscona crucifera: Another orb-weaving species, known as Hentz’s Orbweaver.
Synonyms and Other Common Names
The genus Araneus is also referred to as orb-weaver spiders or, more generally, the angulate and roundshouldered orbweavers4. In addition to their scientific names, some species may have region-specific common names.
Comparison of Common Araneus Species
| Species | Location | Common Name |
|---|---|---|
| Araneus marmoreus | North America | Marbled Orb Weaver |
| Araneus quadratus | Europe | – |
| Araneus saevus | North America | – |
| Neoscona crucifera | North America | Hentz’s Orbweaver |
Notable Characteristics of Araneus Orb Weavers:
- Create spiral, orb-like webs.
- Can be found in various habitats, including gardens, forests, and grasslands.
- They are not aggressive and rarely harmful to humans5.
Distribution and Habitat
Geographical Range
Araneus Orb Weaver spiders can be found across a vast range, including Canada, the United States, and parts of Europe. They inhabit diverse regions in North America, from the cool climate of Alaska to the warm conditions of South Carolina.
In the United States, their presence varies. They are more common in the:
- Northern states like Oregon and Newfoundland
- Western states such as Utah
Preferred Environment
Araneus Orb Weaver spiders are highly adaptable to various environments. They favor:
- Forests
- Gardens
- Wooded areas
- Grasslands
These spiders can often be seen building their webs between trees or on tall vegetation. During late summer and early autumn, they become more visible as they construct larger webs in the surrounding landscape.
Webs and Behavior
Web Construction
Araneus Orb Weavers are known for their intricate and large webs. These orb-weaving spiders construct their webs using a combination of sticky and non-sticky silk. Key features of their webs include:
- Spiral shape
- Radial threads for support
- Sticky silk to catch prey
For example, the Araneus cavaticus species builds large orb webs around twilight, which helps them catch nocturnal insects.
Feeding Habits
As opportunistic predators, Araneus Orb Weavers consume various types of insects they catch in their webs. Common prey includes:
- Flies
- Moths
- Beetles
- Grasshoppers
Araneus Orb Weavers typically immobilize their prey by wrapping it in silk, before injecting it with venom to digest it externally.
Reproduction and Egg-laying
Araneus Orb Weavers reproduce sexually, with males often being much smaller than females. After mating, females lay eggs, which are encased in a protective silken sac. Some details on their reproduction and egg-laying process:
- Males may die after mating
- Female produces multiple egg sacs
- Eggs hatch in spring or summer
- Young spiders disperse via ballooning
In the table below, you can see a comparison of two common Araneus species: the Cross Orbweaver and the Marbled Orbweaver.
| Feature | Cross Orbweaver | Marbled Orbweaver |
|---|---|---|
| Web location | Gardens, building exteriors | Gardens, meadows, dense vegetation |
| Size | 14-20 mm (female), 5-10 mm (male) | 9-20 mm (female) |
| Color | Yellow to brown with a cross pattern | Orange with brown to purple markings |
| Distribution | North America, Europe, and Asia | Northern and Central America, Europe, Asia |
Human-Orb Weaver Interaction
Venom and Bites
Araneus orb-weaver spiders are generally not dangerous to humans. Their venom is meant for immobilizing and consuming prey rather than causing substantial harm to humans. Bites from orb-weavers are rare, but may occur if the spider feels threatened. Symptoms of a bite can include:
- Swelling: mild to moderate swelling around the bite area
- Pain: localized pain that may resemble a bee sting
It is important to note that individual reactions to spider bites can vary.
Natural Pest Control
Orb-weaver spiders, such as the barn spider, are beneficial as natural pest controllers. Their webs efficiently capture many insects that are considered pests, including:
- Flies
- Mosquitoes
- Moths
Having orb-weavers around your garden or property can help reduce the need for chemical pest control methods.
Additional Remarks
- Identification: Orb-weaver spiders can be distinguished by their large, round abdomens and the intricate, circular webs they build.
- Eggs: Female orb-weavers lay their eggs in a protective silken sac, usually on the ground or hidden under vegetation.
- How to know the spiders: Observe their web patterns and body shape to identify them as orb-weavers. Some common types include marbled orb-weavers and cross orb-weavers.
| Spider Type | Markings | Web Location |
|---|---|---|
| Marbled Orbweaver | Orange with brown/purple markings | Trees, tall grasses |
| Cross Orbweaver | Yellow/brown with white cross-shaped spots | Fences, shrubs |
Remember that orb-weaver spiders are more of a help than a hindrance and recognizing their presence can be an indicator of a healthy ecosystem.
Footnotes
Letter 1 – Another Araneas Orb Weaver
Hello!
We have a few of these in our front yard in North Carolina only at night only in the Fall. They spin gigantic webs (roughly 2×2 feet )–but with a very strong anchor webbing that often goes 10-15 feet to the web itself. The spiders are large with a big abdomen,and they have hairs on their legs (as can be seen in the picture). By morning, the webs are gone completely and the spiders can’t be found. They seem somewhat like barn spiders, but the fine-scale concentric web weaving seems different. Let us know what you think they are.
–Zab
Hi Zab,
Tha Barn Spider, Araneas cavaticus, is just one of a large genus known collectively as Orb Weavers. Most have the behavior you describe, including building a large web nightly, and hiding by day. I can’t commit to an exact species in your case.
Letter 2 – Araneas Orb Weaver
Greetings-
This spider has been building a spectacular web outside my parent’s house for the last 2 weeks. Its body is about 1 inch long (head to tail), and about 2 inches from tip of front legs to tip of back legs. It has spots on its back that aren’t obvious in this photo- it builds its web each night and hides during the day so we have had trouble taking its picture! It is a magnificent spider, but we haven’t seen anything like this before (in Cupertino, California) and I we are wondering if it is introduced from somewhere else.
your help will be much appreciated!
cheers,
Karah
Hi Karah,
Your Orb Weaver, Araneas species, is a common spider in the United States as well as other parts of the world. The spiders spin a new web each night.
Letter 3 – Araneus cingulatus
Hi;
Attached are 2 macro photos of a small spider, 1/4" max. which I photographed on the door of my daughter’s car last week. The spider seemed to have an almost "electric" or "International Orange" type yellow/green glow to its abdomen, the photo doesn’t do it justice. My daughter says you may be able to help identify it. Thank You
Jim Pollister
PS-I told my daughter to stop playing with those radioactive materials!!!
PPS: I saw your note about the number of requests your getting. No rush but I really would like to get an answer sometime.
Hi Jim,
If we don’t answer a letter shortly after its arrival, chances are very good it will just get lost in the black hole of our mailbox and get deleted after time. The constant influx of new mail quickly replaces older unanswered mail. We found your spider on BugGuide. This is Araneus cingulatus, and there is no common name.
Letter 4 – Araneus Orb Weaver
Hi I photographed this spider on my deck in NC. He moved from screen door to window to eaves. Could it be a garden orb?
Thanks,
Bill McDearmon
Hi Bill,
You definitely have an Araneus Orb Weaver spider.
Letter 5 – Araneus Orb Weaver
I looked through the collection of spider pictures on your site and could not find one that resembles the spider living in the corner of our patio cover. It is yellowish-orange and has a protrusion on each side of the top of its abdomen. Attached are some photos. Please help identify it and let us know whether or not it is poisonous. Thanks,
Sean
Albuquerque NM
Hi Sean,
This is an Araneus Orb Weaver. It is often very difficult to identify exact species as there is so much variation within individual species. Though all spiders are poisonous, this group does not pose a threat to humans.
Letter 6 – Araneus Orb Weaver
Greetings, and thank you for a truly wonderful site. I have attached photos of a gorgeous orbweaver who has graced my garden all season. She is BIG (the size of a sweet cherry), has an orange abdomen with white spots, a scarlet stripe up the underside, legs of alternating transparent and brown, and fine hairs all over. She takes down substantial prey – junebugs, large grasshoppers and moths, etc. Her web is small – about the size of a salad plate. She is unusual in that she only sits in the middle of her web after dark. She built a hut out of curled peony leaves, and she shelters there throughout the daylight hours and during rainstorms (doesn’t even drop into her web if she snags an insect – she waits until dusk to emerge). The hut-building behavior has me stumped, as well as her rather spectacular coloring. Can you help? Thanks!
Lynn Erickson
Hi Lynn,
This is one of the Araneus Orb Weavers. The species in this genus have variable coloration and we often have problems with exact species identification. The shelter building behavior and coloration tend to indicate either the Marbled Araneus, Araneus marmoreus, or the Shamrock Spider, Araneus trifolium. Petoskey, Michigan
Letter 7 – Araneus Orb Weaver
Hi Bugman,
This picture was taken in August 2006 at my home in Nevada City, CA. It is now January 2007 and Charlotte is still living under our eaves. In fact, she laid a large egg sack this morning. What a great spider to have around for the last 6 months. We will be sad to see her pass on but look forward to the new arrivals (Spring?). I sincerely hope you can find space on your site for this beautiful family member! Cheers,
Kris Crabtree
Hi Kris,
Charlotte is some species of Araneus Orb Weaver.
Letter 8 – Araneus Orb Weaver
While visiting my daughter last week in Cotati, CA, we went to a beach just North of Bodega Bay (which is about 50+ miles north of San Francisco). While walking near the edge of the grassy area and the sand, my daughter spotted this spider. We’ve looked on-line and looked again and again and can’t find any information about it. Can you tell us what type of spider it is. It was among some larger rocks and really stood out because if its red back. I’m sorry the quality of the photos are not good. All I took with me that day with a small 3 pixel camera. I left the good 6 pixel at home (and I’ll not do that again). Thanks!!
Lois Sauer
Rainbow City, AL
Hi Lois,
This is one of the Araneus Orb Weaver spiders. We have problems differentuating the various species. They are harmless spiders.
Letter 9 – Araneus Orb Weaver
I found this in my backyard near Dayton, Oh. I was amazed at how flouresent the orange coloring was. Is it a type of Araneus? cool website!! Thanks
Brian Tesmer
Dayton Oh
Hi Brian,
Indeed, this is an Araneus Orb Weaver, but we have given up trying to identify most specimens to the the species level as there is so much variation within the species. Eric Eaton wrote in to clarify: “The Araneus orb weaver is an emaciated marbled orb weaver, Araneus marmoreus.”
Letter 10 – Araneus species
I found this on my patio wall and it looks like one that I stepped on last month in Scottsdale, AZ. Any ideas?
Thanks,
Kelli Benne
Hi Kelli,
It is one of the Araneus species of Orb Weavers. Harmless.
Letter 11 – Araneus species
Greetings,
I was wondering if you recognize this spider that has recently appeared around my house. It is about one and a half inches from the end of one leg to another and is currently residing in New Hampshire. Thanks for any info!
John
Hi John,
You have an Orb Weaving Spider from the genus Araneus. Sorry I can’t give you an exact species name. She is a female and will probably be laying eggs soon if she hasn’t already. She is harmless.
Letter 12 – Barn Spider, Araneas cavaticus
Don’t really have a question. I took this picture outside my sliding glass door. Sadly, this little guy build his web right where my head would go if I were to go through the doorway. Therefore, he and all his creepy-crally friends are going to have to go (I’ve called and exterminator). He still made for a good photo.
Ted S.
Austin, TX
Hi Ted,
Thanks for the nice photo of what looks like a Barn Spider, Araneas cavaticus. Sorry to hear she is a goner.
Letter 13 – Orb Weaver: Araneus cingulatus
(If you have already opened and read my first message, I offer my sincerest apologies. I did not attach the image in the previous message.)
Hello,
I found this spider on a tomato plant in my backyard today. I realize the photograph is not as high-resolution as it could be, but this spider was only half the size of a grain of rice so it was somewhat difficult to get a good shot with my six megapixel camera. It’s like nothing I’ve seen before, and the yellow and red pattern on its back was astounding in its symmetry and seemed unusually detailed for an insect of this size. The closest thing I could find to it on your site was a spider referred to as Araneus Cingulatus, but, while somewhat similar in color and markings, varies in its size, shape, and type of pattern. Any info on this would be greatly appreciated. Thanks!
Alan K.
Hi Alan,
People are always sending us emails and forgetting to attach the images. This is an Orb Weaver, and it looks to be Araneus cingulatus based on an image posted to BugGuide.
The post Araneus Orb Weaver: Essential Facts and Tips for Enthusiasts appeared first on What's That Bug?.
No comments:
Post a Comment