Queen Butterfly

I see them only once or twice a year here in Texas as the batches travel through. I used to see them more often in CA. Location is key too. Glad I could help sort out the difference. I will watch for you Soldier posting. :)

In direct answer to your rule question. These 3 are not absolute If you read the ID descriptors in the references they are vague with statements like "scattered white dots in the apex". Tomake things worse, here is a reference with specimens of the aberrations in Queens; http://www.butterfliesofamerica.com/danaus_gilippus_thersippus.htm

Yes in that resource there is that photo. Here is another identifier that I used (cheated and did not try to explain both) to determine that this was a queen. In your first photo the underside wing shows a pattern of cell vein consistent with a Queen not a soldier. soldier veins and cells are straighter and more even in size. Again here is a non scientific reference, but has a good visual of what I am saying; http://www.butterflyfunfacts.com/soldierqueendifference.php Compare your Photo 1 to the photo 9 of 22 in the Reference in the suggestion. If still not convinced let me know and we will discuss more. :)

Hello again; Here is a female soldier from Bugguide; they are a little trickier with transparent spots http://bugguide.net/node/view/405004/bgimage You will notice that the two lower transparent spots look like the 3 white lower spots of a Queen, but there are only 2 :)

You requested a "chime in" so here goes... Your second photo of the male (dark scent patches) has 3 white spots on the lower forwing; therefor it is a Queen, male Danaus gilippus. Male Soldier do not have these additional three white spots. Easier to look for than the translucent spots. Not a scientific reference, but has a photo that shows what I just wrote. http://fireflyforest.net/firefly/2005/11/19/queen-butterfly/ :)

This looks a lot like a monarch, too. Great picture!

I think this is more likely a Queen - D. gillipus.