{"id":6393,"date":"2010-06-22T11:53:42","date_gmt":"2010-06-22T16:53:42","guid":{"rendered":"https:\/\/uwm.edu\/field-station\/?p=6393"},"modified":"2017-06-04T15:56:28","modified_gmt":"2017-06-04T20:56:28","slug":"jumping-spider","status":"publish","type":"post","link":"https:\/\/uwm.edu\/field-station\/bug-of-the-week\/jumping-spider\/","title":{"rendered":"Jumping Spider (Family Salticidae)"},"content":{"rendered":"

Salutations, BugFans,<\/p>\n

The Field Guide to Insects of North America<\/em> by Eaton and Kaufman includes a small sampling of non-insect Arthropods. In it, the authors state that jumping spiders are \u201cas cute as spiders get,\u201d and the BugLady totally agrees. It\u2019s easy to wax anthropomorphic about jumping spiders, because when we stare at them, they stare straight back through 8 more-or-less forward-looking eyes. And we get plenty of chances to stare at them, because jumping spiders are very common outdoors and are not averse to coming indoors. They are bold, colorful, diurnal (day-time) hunters with plenty of \u201cattitude.\u201d The BugLady\u2019s mailbox jumping spiders eat the mailbox ants and mailbox earwigs that try to settle there. <\/p>\n

\"Probably<\/a><\/p>\n

Jumping Spiders<\/h3>\n

Jumping spiders (JSs) are true spiders in the family Salticidae, in the order Araneae, in the class Arachnida, in the phylum Arthropoda. The family is a large one, including about 5,000 species worldwide, or about 13% of spider species. Some 300 of those species call the U.S. home. This isn\u2019t their first rodeo; jumping spiders have decorated the planet for about 50 million years and can be found preserved in Baltic amber. Jumping spiders can tolerate a wide range of habitats from the very dry to the very wet and from intertidal zones to mountains, but their hearts are in the tropical forests. <\/p>\n

\"This<\/a><\/p>\n

How do you know if it\u2019s a JS that\u2019s returning your gaze? The gaze itself is accomplished with 8 eyes that are arranged in 3 rows (some authors describe the arrangement as 2 down-curved lines, like 2 \u201cupside-down smiles.\u201d). Two large, forward-facing eyes (the better to see you with, my dear) allow the same type of binocular vision that is enjoyed by birds of prey. Some of the remaining eyes also face forward, and others angle upwards. Bottom line—the JSs can turn its head 45 degrees and can see 360 degrees. It is said to be able to identify prey up to a foot away, and its communication with other spiders depends mostly on visual cues. <\/p>\n

\"Forward-facing<\/a><\/p>\n

JS\u2019s are relatively short-legged. Each leg ends with many tiny hairs, and each of those tiny hairs is further split into many more hairs, and each of those hairs is equipped with an \u201cend foot.\u201d With all those mini-feet, jumping spiders can boldly go where no spider has gone before—like straight up a pane of glass with the end feet gripping, just like a climbing wall, the \u201cimperfections\u201d in the glass. <\/p>\n

\"Ambush!\"<\/a><\/p>\n

JSs don\u2019t spin webs to capture their prey; when they spot a potential meal, they jump.They do spin a silky \u201cdragline\u201d as they jump, for safety. Their jumps may carry them several times up to 40 times their body length (which is admittedly not very long), all without benefit of big, burly leg muscles. The theory is that the spider enjoys some sort of hydraulic assist—contracting the muscles in the front part of its body raises the blood pressure and causes the legs to straighten rapidly. One reference likened it to squeezing the bulb of the toy frog and watching its rubber legs straighten. The BugLady has concluded that it\u2019s magic, like the click beetle\u2019s ability to right itself. <\/p>\n

\"This<\/a><\/p>\n

Notable JSs:<\/p>\n