The term “potato spider” is a common nickname used to describe various invertebrates, rather than a specific scientific species. This colloquial name often leads to confusion, as it can refer to several different creatures that share certain characteristics or are found in similar environments.
Identifying the “Potato Spider”
The primary creature often referred to as a “potato spider” or “potato bug” is the Jerusalem cricket. This insect, belonging to the family Stenopelmatidae, is not a true spider despite its common name. Jerusalem crickets are large insects, measuring 1 to 2 inches in length. They are easily recognized by their large, rounded, humanoid head, and a stout, orangish abdomen with distinct black bands. They possess long, brownish antennae and powerful mandibles, along with six stout legs used for digging.
Another creature sometimes given the “potato spider” nickname is the Woodlouse spider, Dysdera crocata, which unlike the Jerusalem cricket, is a true spider. This spider has a distinctive appearance with a reddish-brown cephalothorax (head and thorax combined) and legs, contrasted by a pale, grayish-white abdomen. Woodlouse spiders are known for their prominent fangs, which are designed to pierce the tough exoskeletons of their prey. Adult females can reach about half an inch in length, while males are slightly smaller.
Habitat and Behavior
The association of these creatures with potatoes stems from their preferred habitats and the circumstances of human encounters. Both Jerusalem crickets and Woodlouse spiders thrive in environments with loose, damp soil. Jerusalem crickets are burrowing insects, often found under rocks, logs, and decaying plant matter, or in gardens and compost piles. They are predominantly nocturnal, spending daylight hours in their underground burrows.
Woodlouse spiders also prefer dark, damp environments and are commonly found under rocks, logs, and in leaf litter, often near their primary food source, woodlice. Like Jerusalem crickets, they are nocturnal hunters and do not spin webs to catch prey. Encounters with these creatures are accidental, often occurring when people are digging in soil for gardening, landscaping, or harvesting root vegetables like potatoes.
Are They Dangerous?
The potential danger posed by these “potato spiders” varies between the two creatures. The Jerusalem cricket is not venomous. While it can inflict a painful defensive bite with its powerful mandibles if handled or threatened, this bite is not medically significant to humans. These insects are not aggressive and prefer to escape rather than bite when disturbed.
The Woodlouse spider, Dysdera crocata, is venomous. However, its venom is not considered medically significant to humans. A bite from a Woodlouse spider causes only localized, temporary pain, redness, or itching, similar to a bee sting or mosquito bite. While their prominent fangs can deliver a noticeable bite, these spiders are also shy and will only bite in self-defense when they feel threatened or are accidentally squeezed.