The Huntsman spider, a member of the family Sparassidae, is known for its large size. These arachnids are found primarily in warmer climates across Australia, Asia, Africa, and the Americas, where they thrive in diverse habitats. Unlike many other spider species, the Huntsman does not construct webs to capture meals, relying instead on speed and agility. This active hunting style earned them the nickname “giant crab spiders” due to their unique, sideways-scuttling motion. Their impressive leg span can reach up to 15 centimeters in some species, setting them apart as one of the larger arachnids humans commonly encounter.
Physical Adaptations for Predation
The Huntsman spider possesses several unique morphological features that make it an effective, cursorial predator, meaning it hunts actively on the ground or surfaces. The most defining characteristic is the arrangement of its legs, which are laterigrade, meaning they extend sideways rather than vertically. This lateral extension gives them a crab-like posture and allows for exceptionally swift movement, including the ability to run sideways and forward with great acceleration.
Their body shape is also noticeably dorsoventrally flattened, an adaptation that allows them to squeeze into and hide within narrow crevices, under loose tree bark, or in wall gaps. This flattened structure is crucial for both evading predators and establishing ambush positions near potential prey. While they do not use silk for capturing prey, their legs are covered in sensitive hairs (setae) that function as vibration and air current sensors. These sensory organs allow the spider to detect the subtle movements of prey from a distance, even in complete darkness.
Primary Prey and Opportunistic Feeding
The diet of the Huntsman spider is composed mainly of insects and other arthropods, reflecting their nature as opportunistic predators. They play a significant role in controlling pest populations, frequently consuming common household pests like cockroaches, crickets, moths, and beetles. Because they are active hunters that pursue their meals, their diet is highly flexible and determined by what is locally available within their habitat.
Huntsman spiders prey on other spiders, including web-building species. The larger species can expand their diet to include small vertebrates when the opportunity arises. This includes geckos, small lizards, and frogs, which they can subdue due to their size and potent venom. These larger meals provide substantial energy, though they are less frequent than their staple insect diet.
Hunting Tactics and Methods
Huntsman spiders employ an active hunting strategy based on stealth, speed, and ambush, distinguishing them from spiders that rely on sticky silk webs. Their hunt begins with stalking, where the spider uses its eight eyes and highly sensitive leg hairs to locate prey. They will slowly creep closer to the target, staying low to the surface to remain undetected.
Once the prey is within striking distance, the Huntsman launches a sudden, rapid pounce to close the distance instantly. This burst of speed is one of their most effective hunting tools, allowing them to overwhelm the prey before it can react. Upon capture, the spider uses its powerful legs and pedipalps to pin the meal down.
The final step involves the use of their chelicerae (mouthparts) to bite and inject venom into the captured organism. The venom quickly immobilizes the prey, and the spider then holds its catch until the venom’s effects are complete. The venom contains enzymes that begin the process of external digestion, liquefying the prey’s internal tissues so the spider can consume the nutrients. This combination of ambush tactics, speed, and paralyzing venom makes the Huntsman spider a successful predator.