Can black widow spiders have triangles instead of hourglasses, if not, what kind can?

Question

I was in my neighbor's backyard looking for something, and I pulled a small tarp off of a grill and a black spider with a red triangle on it's back fell out.

Answer 1

Not all spiders in the widows family have hourglasses as markings. All spiders in the widows family are cobweb weavers and all are poisonous. They can be both black or brown but all have some type of redmarking on their abdomens. It is possible that you have encountered some type of widow spider other the black widow.

Answer 2

Yes, they can. While maturing, the pattern of colors changes.

Answer 3

Black widow spider

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