It's always a thrill for me when I can get close enough to a comma butterfly to actually see the bright white comma mark on the underside of the hindwing. We also spotted an oreas comma (Polygonia oreas, aka Polygonia progne oreas, more information) at Hatton Canyon, and I had hoped my second picture above was from that sighting. Nope. From the topside, the satyr comma has a black spot smack in the center of the hindwing, underneath the two spots along the leading margin. It's easier to tell the difference between the two from the underside. The oreas is almost dark grey and the comma mark is shaped more like a boomerang, rather than the fish hook of the satyr. There's really so many subtle variations of Polygonia in North America that these descriptions wouldn't necessarily work when comparing to other spp.