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Oh, interesting. In which country are you?

Those dimples on her abdomen along with the shiny reddish-black abdomen are generally iconic for Steatoda sp (along with the flattish rounded and overhanging structure of the abdomen). They also generally have a band that goes across the front of the abdomen but can't see that from the angle here.

But yeah, red hourglass-like marking on the underside is a give-away for Widows.

I am in North Texas in the United States. I have caught about a dozen Black Widows from this area. It is my parents property. I even caught one with an egg sack and had the egg sack hatch in a jar. Was quite a site.