(genus Cheiracanthium - Yellow Sac Spider)
Male
1/4 inch
The male Yellow Sac Spiders have longer legs and a thinner, smaller body than the females. These spiders, both male and female, are rumored to be
venomous and should be avoided, but any spider can be bad if you are allergic to the bite. All spiders are beneficial and I don't kill spiders unless
they show aggression, which these never have, or become more abundant in my house than I feel comfortable with. I've had these around my
home for years and just recently found out what they were. They're fast movers and particularly active in the late Spring and early Summer.
They guard their egg sacs and will defend them. © Carol Davis, 6-18-2008
There is a greenish tint to this male Yellow Sac Spider, which happens quite often in the genus Cheiracanthium. I really like this eye-to-eye photo
because it puts you right on his level. © Carol Davis, 6-18-2008
Female
1/3 inch
Two shots of the female who was circling around the central ceiling light fixture in my room. Once in a while
she would zip over to the wall, anchor a web, and go back to the center and keep circling in ever-widening
paths. Very strange. Even stranger, later upon running my hand along the ceiling, there was no
trace of any web that I could feel. © Carol Davis, 5-21-06
On to Yellow Sac Spider Part II >>>
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