Eugene E. Nelson, Bugwood.org
The jumping spiders, as a rule, are relatively small, compact hunting spiders. They have very good eyesight and can pounce on their victims from a great distance. Spiders in the genus Phidippus are the largest-bodied of the salticids. Phidippus audax, the most commonly encountered jumping spider in and around Pennsylvania homes, is found from Canada and the Atlantic Coast states west to California.
P. audax is a black, hairy spider measuring 8 to 19 millimeters for the females and 6 to 13 millimeters for the males. There is a pattern of white, yellow, or orange spots on the top of the abdomen (orange on the younger spiders), and the chelicerae frequently have an iridescent green hue. The males have “eyebrows,” or tufts of hairs over the eyes. Occasionally, white bands extend back from the rear pair of eyes. The eyes located at the center of the front end of the cephalothorax are by far the largest and aid the spiders in capturing prey.
These spiders overwinter as nearly mature, or penultimate, individuals. They mature into adults in April and May, mate, and deposit eggs in June and July. The P. audax female suspends her eggs in a silken sheet within her retreat. In contrast to many other hunting spiders, jumping spiders require daylight to hunt their prey. They can be found on windowsills, tree trunks, and deck railings; under stones; and in other locations during daylight hours.
Bold jumpers are shy spiders that retreat from humans when approached. If handled, they generally do not bite. When bites occur, minor pain, itching, swelling, and redness may persist for one to two days.
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