Get ready to learn about the spiders from the Ctenizidae family! Often called California trapdoor spiders, they live not just in California but all across the United States. These spiders have some pretty neat tricks up their sleeves.
Size:Females are 1.25 inches (3.3 cm) long, while the males appear shorter, measuring 0.75 – 1 inch (1.8 – 2.6 cm).
Color: They come in a wide range of colors, including yellow, brown, and black. These spiders even have a chocolate brown cephalothorax, pale brown abdomen, and black jaws.
Other Characteristic Features: They have a plump body with short and thick legs and a pear-shaped abdomen. The cephalothorax is large and round, with a dimple-like feature at the center. In contrast, their jaw or chelicerae have spiny projections.
After copulation, females lay eggs in the burrows, 7-8 inches deep. The mother takes the utmost care of her eggs, hanging them up on a silk cradle wall.
Spiderlings
After hatching, the spiderlings remain dependent on their mother for a few days, especially during the first winter. Throughout this phase, the mother feeds them. Then they leave their burrows and start building their web.
The Web
Californian trapdoor spiders do not build full-fledged webs; instead, they dig up burrows and make trap gates with their silk.
Are California Trapdoor Spiders Venomous?
Yes, California Trapdoor spiders do have venom. They use it mainly to paralyze their prey. Their venom isn’t dangerous to humans.
Can California Trapdoor Spiders Bite?
Indeed, they can! They might bite if they feel trapped or scared. It’s a good idea to observe them without touching them.
Ecological Importance and Behavior of California Trapdoor Spider
California trapdoor spiders are critical ecological agents, maintaining the insect population and enriching soil quality through their burrowing activities.
Natural Predators: These spiders face predation from various animals, which plays a role in the control of their populations and the broader ecological balance.
Prey-Predator Dynamics: By hunting a variety of invertebrates, they help to regulate these populations, contributing to the ecological health of their habitats.
Relationship with Humans: Despite their venom and capacity to bite, California trapdoor spiders have a relatively peaceful coexistence with humans and can even be part of the pet trade due to their unique characteristics.
Quick Facts
Distribution
California
Habitat
Damp and moist soil
Lifespan
5-20 years
Predators
Scorpions, flies, birds, and centipedes
Web-type
Trap door
Diet
Millipedes, insects and arthropods
Photo Credit: Jeffrey Early
Did You Know
Female Californian trapdoor spiders never go far from their burrows.
Due to their physical similarities, Californian trapdoor spiders often look like mini tarantulas, though they appear shinier.
Despite their aggressive behavior, they are common in the pet trade.
In summary, the California trapdoor spider is a species that showcases the marvels of nature’s engineering and the complex interplay between different organisms within an ecosystem.
A California trapdoor spider has a plump body, a pear-shaped abdomen, and short, thick legs. Its cephalothorax is large and round with a central dimple, while its jaws have spiny projections. Colors range from yellow and brown to black, often with a chocolate brown cephalothorax.
California trapdoor spiders show size differences between sexes. Adult females are the larger of the two, typically reaching 1.25 inches (3.3 cm) in body length. In contrast, the adult males are shorter and more slender, measuring between 0.75 and 1 inch (1.8 – 2.6 cm) long.
Yes, California trapdoor spiders possess venom, but it is not considered dangerous to humans. They primarily use their venom to paralyze and subdue their insect prey. A bite to a person is unlikely to cause a significant medical reaction, though professional consultation is always advised for any spider bite.
No, California trapdoor spiders do not build aerial webs for catching prey. Instead, they are burrowing spiders that excavate tunnels in the ground. They line these burrows with silk and construct a camouflaged, hinged lid or “trapdoor” at the entrance to ambush unsuspecting prey that wanders nearby.
The female California trapdoor spider provides extensive maternal care. She lays her eggs inside her burrow, hanging them on a silk cradle wall for protection. After the spiderlings hatch, they remain with their mother through the first winter, during which time she actively feeds and protects them.
A female California trapdoor spider lays her eggs within the safety of her deep burrow, which is typically 7-8 inches deep. To ensure their protection, she does not simply leave them on the floor but hangs the egg sac up on a silk cradle attached to the burrow wall.
Yes, a California trapdoor spider can bite a person, but this is a rare, defensive action. These spiders are not aggressive and will only bite if they feel trapped, provoked, or directly handled. Their primary response to a threat is to retreat into the safety of their burrow.
Dr. James Watuwa on March 25, 2019.
Spider Team
