This family, Corinnidae, was split from the larger Clubionidae which is where they appear in Kaston. This is one of the members of the genus Castianeira. Peggy Dorris found about 8 of these in Arkansas. Kaston listed 25. This genera along with Corinna and Trachelas are now in this separate family. These are fast spiders. I have tried several times to shoot one as it ran over litter or along tree bark and I have come close. Most do have some resemblance to the ants in motion and activity. They do not build webs. This one is very close to C. amoena. I don't know how variable that species is.