Enumclaw, Forested Unincorporated King County, Washington, USA October 23, 2009 Size: Spider 14mm; Case 20mm
This female was huge when I first collected her. She dropped down from under the eave of the house nearly hitting me in the face as I was going outiside one evening. Her abdomen was so enormous that I immediately assumed she was going to lay eggs soon. So I took her inside and put her in a large jar upside down so that she would lay them on the lid and I'd be able to open the jar and 'inspect' things. She did exactly as I thought she would...within a day of capture, she made her egg case right there on the lid of the jar. It couldn't have taken her very long because there was only about a 3 hour gap of time that I didn't check on her. Her abdomen is now very small and shriveled looking and she firmly stands her ground over her eggs. I take the jar lid and set it on the counter for most of the day so she can get fresh air...and she never leaves it. She won't even move when you touch her.
The egg case is actually pretty hard and very orangish yellow. From looking at it, you would think it might be soft and a little squishy, but it's the opposite. I have always only seen A. diadematus egg cases from a distance and wondered how much of the case is eggs and how much is just silk. But now, even with the case in my hand, I am still left wondering. The mother spider's abdomen is literally only about 1/4 the side it was while pregnant (maybe even smaller). I never had a chance to get a photo of her before she laid the eggs because I thought I had a little more time...but she surprised me and laid them right away.
Contributed by Mandy Howe on 25 October, 2009 - 6:44am Last updated 30 October, 2012 - 1:21am
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