Two most easily confused with it are Acantherus [with longer wider antennae, usually white at the tip; thorax is different on top; and with more slender legs that often show some red color] and Psoloessa texasna [with thicker hind femora, slightly stockier build, and somewhat more vertical face].

I always have a hard time catching / photographing Horesidotes. They dive into the brush (or cacti), are hard to see there, and are very agile, alert things.