I've always considered them to be T. cyaneipennis. They are pretty much the same as the ones found further north in Utah, but to the southeast in Arizona they get a more "opaque" looking wing, with often just a touch of greenish to the blue, and the wings seem to average a little wider.

Sometimes in the Hualapais they are all over the place and abundant from just above the desert up to the top, and you can often hear them flying all around on a good calm day. They are often flying up from the roads as you drive along, and they love the rocky road cuts along the edges of the roads.

T. arizononensis is on rock outcroppings down in the hot desert, and it runs smaller in size. It sounds more like T. pallidipennis when it flies (though admittedly I've only heard a few males make any noise when they flew), and does the circle-back thing more consistently (flying back to the rocks if few off of). In theory T. arizonensis is supposed to have greenish wings, but all I've sound (not that many) have been distinctly blue (though very translucent and not very saturated in color). The dark wing band tends to be less developed, but it's distinct.

Moved from Trimerotropis.