Steatoda grossa
(False Black Widow)

Picture ID 51606

Picture of Steatoda grossa (False Black Widow) - Dorsal

Comments & ID Thoughts

This spider measured about 1/2 inch long. It was found in a desk picked up today at a house in rural Georgia. The spider had laid a couple of egg sacs on the underside of the desk under a drawer which would have been a couple inches off the ground sitting in a garage. The underside of the cephalothorax is a brownish color while the top is dark brown to black. The legs are fairly uniform in color of dark brown or black. When viewed from the side, the abdomen has almost the exact geometric shape of a human brain (really is the best shape to call it). I'm assuming the abdomen is enlarged for whatever reason. There was another more immature spider found with it approximately 1/3" in total length with a more proportionately sized abdomen and clearly of the same species.

From what I can tell, I'm about 85% sure it's the Kukulcania hibernalis "Southern House Spider," but there is such variation of coloration of photos I've seen online. It has barely noticeable bristles on its abdomen when viewed up close and barely discernible bristles on the legs.

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TangledWeb

Hi, I’m not sure. She might be Steatoda grossa, a false black widow. The abdomen is probably big because it is female gravid with eggs. The other spider could be a male. They are usually significantly smaller than the females. If possible, a picture of them together would be great. More people have yet to see your photo and comment.

Additional Pictures

Picture of Steatoda grossa (False Black Widow) Enlarge Picture
Picture of Steatoda grossa (False Black Widow) - Male - Dorsal Enlarge Picture
Picture of Steatoda grossa (False Black Widow) - Dorsal Enlarge Picture
Picture of Steatoda grossa (False Black Widow) Enlarge Picture