Giant House (Eratigena atrica)

Discover fascinating details about the Giant house spiders! Part of the Eratigena genus, these spiders may have a large appearance, but they’re actually quite harmless. They have simple eyesight, only distinguishing between light and shadow. True to their name, these spiders often make our homes their own.

Scientific Classification

• Family: Agelenidae
• Genus: Eratigena
• Scientific name: Eratigena atrica

Physical Description  and Identification

Adults

• Size: Females are around 0.7 in (18 mm) while males are 0.39-0.59 in (10-15 mm). The leg span of females is around 2 inches (45-50 mm) while males have 0.9 in-3 in (25-75 mm).
• Color: The entire body is beige, brown, or orange with the sternum having three beige, gray, or brown dots on its two sides. The posterior or the opisthosoma has a line with six dots on each side.
• Other Characteristic Features: The legs, abdomen, and palps are hairy. Eight eyes are settled in two rows and all are of the same size.

Eggs

40-60 eggs are released in a single sac.

Spiderlings

All spiderlings stay together for around a month. Each of them goes through the molting phase at least 8-10 times before becoming mature.

Are Giant House Spiders Venomous?

Yes, Giant House Spiders are venomous, but their venom is not harmful to humans.

Can Giant House Spiders Bite?

Yes, they can bite, but it’s rare. If they do bite, it’s usually not severe and is similar to a bee sting. The pain of agatoxin doesn’t generally last for more than a couple of hours.

Ecological Importance and Behavior of Giant House Spider

Giant House Spiders play a crucial role in regulating insect populations, acting as natural pest controllers in our homes. Their presence contributes to a balanced ecosystem, even within human dwellings. They exhibit a nocturnal lifestyle, actively hunting their prey during the night and retreating to their funnel-shaped webs during the day.

Natural Predator: Despite their size, Giant House Spiders are not without their threats. Birds and larger arachnids stand as their natural predators, keeping their population in check.

Prey-Predator Dynamics: Their hunting prowess, combined with their intricate web design, establishes them as effective predators of insects, helping to maintain a harmonious balance in their chosen habitats.

Relationship with Humans: The relationship between humans and Giant House Spiders is a fascinating one. While their presence in our homes may be unnerving to some, they contribute positively by reducing the number of pests. Educating the public on the harmless nature of these spiders can foster a mutualistic coexistence, reducing unfounded fears and promoting a better understanding of their role in our environment.

Quick Facts
Distribution	Northern Africa, Central Asia, and Europe
Habitat	Rocks or caves of dry forests
Web Type	Funnel-web
Poison Fact	Non-toxic to Human
Diet	Blowflies, fruit flies, moths, wasps,
Mode of Reproduction	Oviparous
Number of Eggs	Around 60
Lifespan	2-3 years, sometimes around 6 years
IUCN Conservation Status	Not listed

Did You Know

• The giant house spider was once enlisted in the Guinness Book of World Records for its speed (1.18 mph).
• It is often confused with another spider species namely hobo spider due to their similar appearance.
• The giant house spider was previously included in the genus known as Tegenaria.

In wrapping up, the Giant House Spider stands as a testament to the intricate balance of nature, showcasing how even the most unlikely of species can find a home amidst human civilization.