I think she’s a Brown Widow, Latrodectus geometricus. The second choice is an immature Western Black Widow, Latrodectus hesperus. I can’t find evidence that Brown Widows have populations in Mexico YET. They are spreading in Southern California. https://cisr.ucr.edu/invasive-species/brown-widow-spider As the article in the link says, the best way to tell the two species apart (without a microscope) is from the shape of the egg sac. If you find a spiky tan egg sac please send a photo to document the spread of Brown Widows. Thank you for posting the photo, I’m sorry that I’m not certain which species she is.