Green crab spiders are common in gardens and natural areas, often blending seamlessly with their surroundings. People frequently encounter these arachnids, leading to questions about their potential danger. This article explores their characteristics and clarifies whether they pose a threat to humans.
Identifying Green Crab Spiders
Green crab spiders (Misumessus oblongus) are identifiable by distinct features. Females typically measure 3/16 to 1/4 inch (4.45 to 6.01 mm) in body length, while males are noticeably smaller, around 1/8 inch (2.56 to 2.96 mm). Their coloration ranges from pale green to silvery white, sometimes with pink or red markings. Some species can even change color to match their environment, like flowers.
These spiders get their name from their flattened, oval, crab-like bodies and how they hold their first two pairs of legs extended to the sides. These front legs are often thicker and longer, allowing them to move sideways, backward, and forward. Unlike many other spiders, green crab spiders do not spin webs to catch prey. Instead, they are ambush predators found on leaves of shrubs, herbaceous plants, or within flowers, waiting for insects.
Are They Harmful to Humans?
Green crab spiders are not dangerous to humans. Their venom, effective for immobilizing small insect prey, typically has minimal effect on humans. Bites are rare and usually occur only in self-defense if the spider feels threatened or is accidentally pressed against the skin.
If a bite occurs, the reaction is usually mild and localized, similar to a bee sting. Symptoms may include slight redness, minor swelling, or localized pain at the bite site. These symptoms are generally not life-threatening and typically do not require medical intervention. These non-aggressive spiders prefer to avoid confrontation and will usually attempt to flee rather than bite.
Encountering a Green Crab Spider
Encountering a green crab spider in your garden or home is usually not a cause for concern. These spiders are beneficial predators, controlling garden pests like mosquitoes and flies. Leave them undisturbed, allowing them to continue their role in the ecosystem.
If a green crab spider needs relocation indoors, a gentle approach is best. Guide the spider into a cup and release it outdoors in a suitable habitat, such as a garden or among plants. Their presence indicates a healthy outdoor environment, and there is no need for alarm.