Trapdoor spiders are very difficult to locate as the nearby vegetation and soil offer a natural camouflage to these species. The trapdoors are typically nocturnal hunters and they wait for the prey to approach their door.
These spiders usually prey on arthropods, tiny vertebrates, and small insects. It’s the vibration that warns the spider of any prey and when the prey comes close enough to capture, the trapdoor pops up suddenly and hold it.
Unlike males, females are not known to travel farther from their burrows too often especially when they have an egg sac. The female typically captures food and regurgitates it to feed its young. The burrow entrances are perfectly camouflaged where females live for several years.
Trapdoor spiders are often devoured by the spider wasps that reach out their burrows to gain entrance.
It takes several years for trapdoors to get mature. Females are known to live longer as compared to males. The female trapdoors occasionally leave their burrows. The males typically come out after heavy rain when there are greater chances of finding prey.
These spiders display shiny brownish or black colour with the length measuring at 25 mm. The males are fairly smaller than females. However, the males have longer legs and being more slender as compared to those of females.
Unlike males, females for the most part live in burrows while digging 4 – 10 inches (10 – 25 cm) straight into the ground. The width of the burrows usually measures around 0.5 inches (13 mm). The burrow’s width is enough for spiders to turn around inside. They employ an array of spines on their chelicerae known as rostellum to cut beyond the soil, which is conveyed to the surface for disposal.
The trapdoor levels insides of the burrows while using its fangs, after which it lines the walls with a compact sheet of velvety silk. There are several trapdoor species that make use of the soil to frame a plug-like thick door. There are skewed edges on the door that fit closely into the burrow entrance. Other spider species tend to make a rather wafer-thin door which frames sloppily into the burrow entrance.
The materials used for covering the door includes soil, lichen such as fungi and algae and is perfectly camouflaged when it’s shut. There are spiders that hold tightly the doors with the help of fangs while pushing against the burrow walls with legs.
Trapdoor spiders are often attacked by parasites including small-headed flies, raccoons, skunks, and coatis.
The average lifespan of these spiders is 5 – 20 years.
In general, these spiders are not aggressive but they can when provoked and as such, they rarely bite.
Story by Ben Delport – Head Guide