The brown recluse spider often sparks widespread concern due to its venomous bite. Many wonder about its presence in different regions, particularly in Washington State. This anxiety is understandable, given the potential for its bite to cause skin lesions.
Brown Recluse Presence in Washington
Despite common misconceptions, the brown recluse spider (Loxosceles reclusa) is not native or established in Washington State. Reported sightings are almost always misidentifications of other common spiders or isolated instances where a brown recluse was transported but did not establish a breeding population. The brown recluse’s established range is primarily in the south-central United States, encompassing states like Kansas, Oklahoma, Texas, Missouri, and parts of the Midwest and Southeast. Entomologists and state health departments in Washington consistently confirm the absence of established brown recluse populations.
Spiders Commonly Mistaken for Brown Recluse
In Washington State, several local spider species are frequently confused with the brown recluse. The hobo spider (Eratigena agrestis) is one such spider, often mistaken due to its brownish coloration. Hobo spiders have eight eyes arranged in two rows, unlike the brown recluse’s distinct eye pattern. While hobo spiders can bite, their venom is not considered medically significant.
Another spider often confused with the brown recluse is the giant house spider (Eratigena atrica), known for its large size and rapid movement. These spiders are larger than brown recluses and, like hobo spiders, possess eight eyes. Various other brown-colored house spiders, including some wolf spiders or yellow sac spiders, may also be misidentified due to their general appearance. While some of these spiders may bite if provoked, their venom is not associated with the severe tissue damage seen in brown recluse bites.
Identifying a Brown Recluse
Even though the brown recluse is not established in Washington, understanding its key identifying features can be helpful. The most notable characteristic is a dark, violin-shaped marking on its cephalothorax, the fused head and thorax region. The “neck” of this violin shape points towards the spider’s abdomen. However, this marking can vary in intensity and may not be present in younger spiders, making it an unreliable sole identifier.
A more definitive feature is the brown recluse’s eye arrangement: it has six eyes arranged in three pairs in a semicircle, unlike the eight eyes most other spiders possess. Brown recluses also have uniformly colored bodies and legs, typically light to dark brown, without stripes, bands, or other patterns. Their legs are covered in fine hairs but lack prominent spines. The body of an adult brown recluse is relatively small, ranging from 0.25 to 0.5 inches long, excluding its legs.
Suspected Spider Bites
Most spider bites are harmless, causing only minor irritation such as redness, swelling, or pain at the bite site. For typical spider bites, it is advisable to clean the area with mild soap and water. Applying a cold compress or ice pack can help reduce swelling and discomfort. Elevating the affected limb may also be beneficial.
Seek medical attention if symptoms worsen, or if there are signs of infection such as increasing redness, pain, warmth, pus, or red streaks spreading from the bite. Immediate medical care is also important if systemic reactions occur, including fever, chills, body aches, severe pain, cramping, or difficulty breathing or swallowing. It is also recommended to consult a healthcare professional if you suspect a bite from a medically significant spider, or if you are unsure of the spider species involved.