The world of spiders often evokes both fascination and apprehension, particularly when considering their larger representatives. Exploring the largest spiders reveals a remarkable diversity in form and adaptation. This journey into the realm of giant spiders highlights their impressive physical attributes and unique ways of life across different global habitats.
Understanding Spider Size Measurements
Discussions about the “biggest” spiders typically involve two distinct measurements: leg span and body mass. Leg span refers to the distance covered by a spider’s outstretched legs, measured from the tip of the front leg to the tip of the opposing back leg. This measurement provides an understanding of the spider’s overall reach. Body mass, on the other hand, quantifies the spider’s actual weight and bulk.
These distinctions are important because the spider with the longest leg span may not be the heaviest, and vice versa. Some species are slender with expansive limbs, while others possess compact, heavy bodies. Recognizing these differences helps accurately categorize and appreciate the various forms of large spiders.
Spiders with the Longest Leg Span
The Giant Huntsman Spider, Heteropoda maxima, holds the record for the largest leg span among all known spider species. Discovered in a cave in Laos in 2001, its legs can stretch up to 30 centimeters (approximately 12 inches), comparable to a dinner plate. Its body length is more modest, measuring about 4.6 centimeters (1.8 inches). These spiders are characterized by yellowish-brown coloration and irregular dark spots, with legs that twist forward in a crab-like manner, earning them the nickname “giant crab spiders.”
Unlike many other spiders, the Giant Huntsman does not build webs to catch prey. Instead, it actively hunts, using its speed and agility to pursue and capture insects and other invertebrates. Its flattened body and nimble legs enable it to navigate tight crevices within its natural cave habitat.
Spiders with the Greatest Body Mass
When considering sheer bulk, the Goliath Birdeater, Theraphosa blondi, stands as the heaviest known spider in the world. This tarantula can weigh up to 175 grams (6.2 ounces), a mass comparable to a regulation pocket billiards ball or even a small puppy. Its robust body can reach lengths of up to 13 centimeters (5.1 inches), roughly the size of a human fist. While its leg span can extend up to 30 centimeters (12 inches), it is generally considered second in leg span to the Giant Huntsman.
Native to the tropical rainforests of northern South America, including Venezuela, Guyana, Suriname, and Brazil, the Goliath Birdeater is a terrestrial, nocturnal spider. It constructs deep burrows in marshy or swampy areas within the rainforest floor. Despite its common name, which originated from an 18th-century engraving depicting one eating a hummingbird, its diet primarily consists of large arthropods, worms, amphibians, and small rodents, with birds rarely being a significant food source.
Living with Giant Spiders
Encounters with giant spiders in their natural habitats are generally uncommon, as many are nocturnal and burrowing. Both the Giant Huntsman and the Goliath Birdeater are typically solitary creatures. While their size might appear intimidating, these spiders are not inherently aggressive towards humans and usually bite only when provoked or feeling threatened.
The venom of these large spiders is not considered dangerous to humans. A bite from a Goliath Birdeater, for instance, is often compared to a wasp or bee sting, causing localized pain and swelling. The primary defense mechanism of the Goliath Birdeater is its urticating hairs, which it can flick off its abdomen, causing irritation and itching upon contact. The venom of the Giant Huntsman Spider also typically results in mild symptoms such as pain, swelling, and itchiness.