Steatoda triangulosa
(Triangulate Cobweb Spider)

Comments & ID Thoughts

I apologize for the bad quality. The spider is about a quarter of an inch in length--perhaps slightly larger. It is dark brown/black in color with light brown markings along its abdomen, similar to that of a Redbacked Spider. It also has light-colored legs, with dark spots at the joints. I presume it is male, but I am not quite sure. When touched, it curled into a ball for a while.

I found it crawling up the wall of my stairwell to the basement while I was watching a video of a man opening Redbacked Spider egg sacs, ironically. I have been trying to identify the spiders in my home for the past 7 months, and this one struck me as new.

I am assuming it is a species of widow spider, but there are no images online that really depict its coloring and detail such as this one that I have found. Most have red or complex markings, but this one is just a brown coloration of the typical red markings, however remaining dark colored as a whole.

Please let me know if you need any more information or images (if possible). Thank you.

• Submitted by: 
  
  hawklen1326
• Submitted: Feb 16, 2018
• Photographed: Feb 16, 2018
• Spider: Steatoda triangulosa (Triangulate Cobweb Spider)
• Location: Oxford, Michigan, United States
• Spotted Indoors: Basement or Cellar
• Found in web?: No
• Attributes: Dorsal