Two images, one of a male and one of a female Monarch. We've had some 5 to 7 Monarchs visiting our backyard flower patch for over a week now. Almost all were males. I only saw a female once but wasn't able to get a shot of her. I had to retrieve a file photo of a female for comparison with the male.
Top image: A male Monarch. Note the two black spots on its wings, one on each side of its body. These spots are present in males only.
Female Monarch. Note the absence of the black spots on the wings of the female.