The huntsman spider, a member of the family Sparassidae, is an arachnid known globally for its large size. Many species can reach a leg span of up to 15 centimeters, with the giant huntsman spider (Heteropoda maxima) having a record span of nearly 30 centimeters. Its size, combined with its habit of darting across walls and ceilings, often prompts questions about its physical capabilities. Huntsman locomotion is defined by speed and agility rather than leaping ability.
Clarifying the Huntsman’s Movement
Huntsman spiders are not classified as true jumping spiders, unlike the family Salticidae, which uses a specialized hydraulic system to launch itself. Movements observed from a huntsman are typically an extremely fast lunge or launch that is easily mistaken for a controlled jump. When attacking prey or escaping an immediate threat, the spider employs a rapid burst of energy that propels its body a short distance.
This short-range propulsion is different from the precise, long-distance leaps of jumping spiders. The huntsman’s maneuver often involves simply letting go of a surface and pushing off, sometimes described as a controlled fall, to instantly change its location. High-speed running remains the primary method of movement, with any aerial movement being a secondary, emergency tactic.
Anatomy and Record-Breaking Speed
The huntsman spider’s speed results directly from its specialized limb structure, known as the laterigrade leg orientation. This means the leg joints are twisted, causing the legs to extend out to the sides in a crab-like fashion rather than hinging vertically. This lateral orientation allows for a low-profile stance and incredible mobility in all directions, including sideways movement.
This structure allows the spider to squeeze into narrow crevices and provides the leverage for its remarkable velocity. Huntsman spiders are among the fastest spiders in the world, with some species capable of running up to one meter per second. For the largest specimens, this translates to a speed of up to 40 times their own body length every second.
Habitat and Hunting Behavior
The huntsman’s speed and flat body shape dictate its preferred habitat and hunting style, as it does not rely on a sticky web to capture food. These spiders are active pursuit predators, utilizing their agility to chase down and overpower their meals. They typically hunt small invertebrates, such as cockroaches, moths, and other insects, and occasionally small lizards or geckos.
They often reside in concealed places like under loose tree bark, beneath rocks, or in the crevices of man-made structures. Their flattened bodies allow them to slip into narrow gaps, which is why they are frequently encountered indoors, hiding behind furniture or in vehicle sun visors. Once a huntsman detects prey, it uses its explosive speed to close the distance, capture the prey with its powerful legs, and immediately inject venom through its fangs.
Toxicity and Interaction with Humans
Despite their size, huntsman spiders possess venom that has low medical significance to humans. The venom is designed primarily to immobilize the small insect prey they pursue, not to cause serious harm to larger mammals. A bite results in mild, localized symptoms, such as temporary pain, redness, and swelling at the site.
The species is known for its shy temperament and tendency to flee rather than confront a threat. Bites usually occur only when the spider feels trapped or is protecting its egg sac, such as when accidentally pressed against human skin. In rare cases, individuals may experience systemic reactions like nausea or headache, but severe complications are uncommon. Huntsman spiders are regarded as beneficial inhabitants that help control household insect populations.