Arrow Shaped Micrathena Spider (Micrathena sagitatta)
*Abdomen = butt, Thorax = middle section, Cephlathorax = head and thorax.*
This insect is uncommon to find in the state of Maine.
Like all other female Micrathena spiders, this one gets the pretty looks. As you can see, this species of spider has an arrow shaped abdomen. These spikes are just for looks and detering would-be predators to the spider. (No, the spikes are not poisonous but I do not recommend touching them.) There is also a smaller pair of spikes in the female spider where the abdomen connects to the thorax.
The spider makes an orb-shaped web, the same type as lots of other spiders make. The male type of spider has no spikes whatsoever and the abdomen is rounded. Males are also two times smaller than the female and are mostly black whith edges of white. The underside of the spider has the web-spinning glands that make silk for the spider to make its web, and the rest of the females underside is yellowish with four smaller red and black spikes.
When autumn comes, the spiders find mates for the next generation of spiders. After they mate, the female goes onto a leaf, generally by her web, and lays her eggs. She stays with the eggs until winter, then dies. Over winter, the egg sac grows as the eggs inside grow bigger. When the egg hatches in spring, the baby spiders all seperate and find habitats with vegetation as a place to hide, spin a web and grow. Try looking in dense vegetation for them. I found mine in a bush of ferns, milkweed and pachysandra.
If you find one, Please DO NOT TOUCH THE WEB. These spiders work very hard every single day to re-spin their web. If it bites you, do not worry. It is not venomous and the bite may sting at first, but it is no more worse than a mosquito bite. As I said before, the spines on the spider are not poisonous, but do not touch them. I think these spiders are just one of many beautiful garden-dwelling spiders that dwell in out backyards (if you live in Maine).