Many of the spiders we commonly call orb-weavers belong to the genus Araneus. Famous for their amazing geometric orb webs, these spiders can often be spotted hanging upside down in the centre of their webs or hiding in a retreat at the side. Currently (as of 2023), 560 species of Araneus are recognised. Spiders in this genus are amongst the most visible and visually striking of spider species, including a number of species that are readily recognised around the world (e.g. the Garden Cross Spider, Araneus diadematus).
Many of the spiders in this genus used to be known by the name ‘Epeira’, though we now recognise that the name ‘Araneus’ is older and is the correct genus name. Let’s look a little closer and learn some cool facts about these amazing spiders!
Size: Females are around 1 in (2.54 cm) and males are maximum 0.3 in (0.76 cm).
Color: Brown or tan-colored bodies with black, white, and brown-banded legs.
Other Characteristic Features: Male spiders have longer legs and smaller but more elongated abdomens than females. The pedipalps of male spiders have noodles with a hook shape. The external genital structure of female spiders has a long appendage.
Eggs
Female spiders make a silken sac and lay about 100 eggs in them.
Spiderlings
The eggs overwinter and hatch afterward. Spiderlings of many species are yellow. Following sibling cannibalism and survival, the spiderlings make a single silk strand and disperse through the process of “ballooning.”
The Web
The spiders of this genus mostly make spiral or wheel-shaped webs like most orb-weavers.
Are Araneus Spiders Venomous?
Yes, Araneus spiders are venomous. They use their venom to immobilize and digest their prey.
Can Araneus Spiders Bite?
Araneus spiders can bite if they feel threatened, but their bite is usually harmless to humans and might cause slight discomfort or itching.
Ecological Importance and Behavior of Araneus spider
Araneus spiders play a crucial role in controlling insect populations, contributing to the balance of ecosystems. They exhibit fascinating behaviors, from their web-building skills to their unique survival strategies.
Natural Predators: Birds and larger insects often prey on Araneus spiders, highlighting their position within the food web.
Prey-Predator Dynamics: These spiders rely on their venom and web-building prowess to capture prey, while their cryptic coloration and agility help them evade predators.
Relationship with Humans: Araneus spiders, despite their ability to bite, are generally harmless to humans and can actually be beneficial in controlling insect populations around homes and gardens. Educating the public about these spiders can foster a harmonious coexistence and appreciation for their ecological role.
Quick Facts
Distribution
America, Asia, and Africa
Habitat
Under woods and leaf litter
Diet
Insects and other spiders
Web Type
Orb web
Lifespan
Around 1 year
IUCN Red List Status
1 species currently assessed [<0.2% of genus]
Did You Know
Jewel spider (Araneus gemmoides), a species of this genus, is known to change its color according to the seasons.
Swedish arachnologist, and entomologist Carl Alexander Clerck described this genus in 1757.
A short documentary, Epeira diadema based on the European garden spider (Araneus diadematus) belonging to this genus, was in the nomination for an Oscar in 1953. It was directed by Alberto Ancilotto, an Italian director.
Male spiders often play dead to defend themselves from predators.
In summary, Araneus spiders, with their remarkable web-building abilities and significant role in ecosystems, offer a captivating glimpse into the world of arachnids and underscore the importance of preserving biodiversity.
The main characteristic of an Araneus spider is its creation of large, geometric, wheel-shaped orb webs. These spiders are often found hanging upside down in the web’s center or hiding in a nearby retreat. The genus is highly diverse, with 560 recognized species as of 2023.
There are 560 recognized species within the Araneus genus as of 2023, making it one of the largest and most widespread genera of orb-weaver spiders. This large number reflects their successful adaptation to various environments and ecosystems on a global scale, with many species yet to be studied.
Araneus spiders hang upside down in their webs for stability and to react quickly to prey. This posture allows them to use gravity to their advantage when dropping onto insects caught below. It also presents a smaller silhouette to aerial predators like birds, improving their chances of survival.
No, while all Araneus spiders are orb-weavers, not all orb-weavers belong to the Araneus genus. “Orb-weaver” is a general term for any spider that builds a circular web, a group which includes many different genera and families. Araneus is simply one of the most common and recognizable genera.
The Araneus genus of spiders was previously known by the scientific name ‘Epeira’. Through taxonomic review, it was determined that the name ‘Araneus’ was older and therefore had priority according to the rules of scientific nomenclature. ‘Epeira’ is now considered a junior synonym for the genus.
You can identify the web of an Araneus spider by its classic orb shape, featuring a spiral design with radial support lines like the spokes of a wheel. These webs are often large, vertically oriented, and built in open areas between plants or structures to effectively intercept flying insects.
No, the Araneus diadematus, or Garden Cross Spider, is not considered dangerous to humans. Like most spiders, it is venomous, but its bite is rare and typically results in only minor, localized symptoms similar to a bee sting. For any specific medical concerns, always consult a healthcare professional.
Dr Richard J. Pearce (PhD) on September 11, 2019.
Spider Team
