An Australian huntsman spider. Credit: Sandra Caldwell | Shutterstock. Huntsman spiders are large, fast spiders distributed in warm climates throughout the world. They are notable for the way that they catch their prey. Huntsman spiders don't build webs to catch prey, explained entomologist Christy Bills, Invertebrate Collections manager at the Natural History Museum of Utah. Rather, they hunt down their prey, a habit that gives them their common name. There are thousands of subspecies in this family (Sparassidae). The average huntsman spider species is about 1 inch (2.5 centimeters) long with a leg span of up to 5 inches (12.7 cm).