This was easy to key to Thanatus vulgaris using Dondale & Redner 1978. These spiders have made residence in a pet store in north Austin. I was told that the spiders regularly drop on a line into the cricket bins, snag a cricket, and then steal up on the line out of the bin.

Dondale & Redner reports that it's range is "California to Mexico and Georsia. northward to Idaho. Ohio. and Massachusetts; Europe, North Africa." Furthermore, "Specimens of vulgaris have been collected from shrubs, buildings such as railroad stations, grocery stores, and restaurants, and ships at sea. The species is probably introduced in North America."