The "Insect" of the week
The Jumping Spider
Photo (c) Wayne Madison at the Tree of Life.orgHello all! Today we have a very special addition of the "insect of the week". As an ode to Dick Walton (naturalist, generalist, and humorist), I've decided to do a blog about Jumping Spiders! Although they are not insects, they are closely related to insects. Below is the taxonomy of jumping spiders:
Kingdom: Animalia (just like insects)
Phylum: Arthropoda (again like insects)
Class: Arachnida (ooh there's the difference! Insects are class Insecta)
Order: Aranae (all spiders)
Family: Salticidae
Dick Walton has done a lot of interesting research on these little guys and they really are quite fascinating. You may not like spiders, but how can one resist the jumping spider? Observe the cute and cuddly Phidippus audax:
This guy, also known as the bold jumping spider, is very common in Cape May but how often do we really pay attention to P. audax or any jumping spider? Jumping spiders are extremely diverse and numerous. There is an estimated 5,000 species of Salticids in the world! The main feature that sets them apart from other spiders is their eyes. They have eight eyes in all, but the front row of four are enlarged and powerful giving them stereoscopic vision. If you find a jumping spider it will often turn and look directly at you. They see us, and quite well!
This advance vision gives Salticids an advantage when hunting for prey that is relatively far away. They have a powerful concentration of muscles in the front of their bodies that gives them the ability to jump more than fifty times their body length. The jumping spider is also one of the few spiders that can actually climb on most surfaces, including glass. Although they don't spin webs in the general sense, salticids do use silk for a variety of reasons. When patrolling territory, whether looking for a mate or hunting, the jumping spider will lay out a line of silk. This works as a kind of a safety line that allows the spider to travel anywhere without fear of falling. They also will weave tent-like shelters out of silk where the female will go to lay eggs. Both sexes will also use the shelter when they need a safe place to molt.
One last thing I want to mention about salticids is their interesting dimorphic appearance and intricate courtship process. Males often have bright coloration or other flashy modifications that females lack. Males will use these attributes in an elaborate courtship dance. This dance is different than most spiders due to to the salticids advanced vision. To see video of this visit this website. Many jumping spiders will also mimic other insects/arthropods, including ants, some beetles, and even pseudoscorpions!
The four spiders that are shown above, Platycryptus undatus, Phidippus audax, Eris flava, and Metacryba taeniola are all very common species of jumping spiders that you can see around Cape May. They are amazing creatures and they are right in our own backyard. Lucky us!
To see more visit Dick Walton's website: www.rkwalton.com
All photographs above provided by Dick Walton
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