Spiny orb weaver spiders, with their distinctive shapes and vibrant colors, often draw attention and curiosity. Their unusual appearance, featuring a flattened, disc-like body often adorned with prominent spines, can lead many to wonder if these creatures pose a danger. Understanding the true nature of spiny orb weavers is important for coexisting with these fascinating arachnids.
Identifying Spiny Orb Weavers
Spiny orb weavers are recognized by their unique physical characteristics. Females, the more commonly seen individuals, typically have a broad, flat abdomen with six pointed spines protruding from the edges, giving them a crab-like appearance. Their body colors are often bright and contrasting, ranging from white, yellow, or orange to red and black, sometimes with black spots. Females usually measure between 5 to 10 millimeters in body length, while males are significantly smaller, around 2 to 3 millimeters, and lack the pronounced abdominal spines.
These spiders construct circular orb webs, which can be large, sometimes reaching up to 60 centimeters in diameter. They often rebuild their webs daily, typically in gardens, shrubs, trees, and occasionally on the corners of buildings. Spiny orb weavers are found in warm climates, including the southeastern United States, often inhabiting wooded areas, citrus groves, and garden spaces where they can anchor their webs.
The Nature of Their Venom
Like most spiders, spiny orb weavers possess venom. However, their venom is primarily adapted to immobilize the small insect prey they catch in their webs, such as flies, mosquitoes, beetles, and moths. For humans, their venom is not considered medically significant or harmful. Their venom’s composition and potency are mild, not strong enough to cause severe reactions in people.
If a bite occurs, symptoms are typically minimal and localized, often described as similar to a mild bee sting. Spiny orb weavers are not aggressive and are reluctant to bite humans unless they feel directly threatened or are accidentally squeezed. Their primary defense is to escape or remain still, rather than engage with a perceived threat. This makes bites rare occurrences.
What to Do if Bitten
Should a bite happen, the symptoms are usually mild and temporary. These may include localized pain, itching, redness, or slight swelling at the bite site. Any discomfort typically resolves quickly on its own.
For such a bite, basic first aid is usually sufficient. Clean the affected area with mild soap and water. Applying a cold compress can help reduce pain or swelling. Over-the-counter pain relievers or antihistamines may manage mild discomfort or itching.
Medical attention is almost never necessary, unless an individual experiences a rare allergic reaction or symptoms worsen. These spiders are beneficial predators, helping control insect populations, and can often be safely relocated.