Wednesday, October 5, 2011

Nursery Web Spider (Pisaurina mira)

Pisauriana mira (Nursery Web Spider) are very common and often seen scurrying along the forest floor. They are in the Family Pisauridae and about the same size as Wolf Spiders.

Nursery Web Spiders are often found in gardens and you can see below one in my leaf lettuce that looks fat and full of eggs. I read that they eat a lot of those tarnished plant bugs and other garden insect pests.

Here is a link to an earlier blog I did on spider egg sacs: You can scroll down and see the Pisauriana carrying her egg sac to a good location.

The interesting thing about Nursery Web spiders is, well, the nursery. After carrying around the sac of eggs she finds a good location and begins by tying leaves together with silk. She then suspends her egg sac within and waits nearby for them to hatch. I believe she stays on guard at least until after their first molt, about a week. I find this interesting because most insects that lay and abundance of eggs don’t protect their offspring. The thinking is that there are so many, so they play the odds that enough will survive but not Pisaurina mira, she hangs in there to ensure survival.

Here is an addition to my previous post on spider eggs sacs. This is not a large furry egg but rather a large group of spiderlings huddled together.  When I approached they all scattered.  You can see the recently molted skins.

When the male Pisaurina mira come courting he brings his intended a fly as a gift. He is planning on having his way with her while she is eats and not be interesting in eating him. I would love to see this in action but so far no luck. 

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1 comment:

Michelle said...

This is an amazing post as is the one about eggs sacs. I will have to get the book you mentioned as I have become very interested in the insects in my yard. I now know that it was a nursery spider that dropped into my lap literally late this spring. I didn't know what it was at the time and am glad I am not longer afraid of spider. Thank you for adding this to Nature Notes...Michelle