It's one of the largest (females reach 22mm) and most striking spider here in the Mediterranean basin. As you can see from the pic, females are jet black with shiny green chelicerae, while male are smaller and more leggy, have a grayer abdomen and bronzish chelicerae. Belonging to the Segestriidae family, it lives in silken tubes with radiating trip lines at the entrance. It's an awesome spider to keep, very long lived and very reactive.
You do have your local segestriids in the US belonging both to the genus Segestria and Ariadna. However being very sedenteray spiders, just like the Mediterranean species, while not uncommon, they are locally distributed.