Do you see the difference?

It is quite easy to distinguish between a female and a male monarch butterfly if you look closely at their wings. Here are the main differences:
‍

Black scent glands:

-Male On the hind wings, males have a small black spot on each wing, near the center of the wings. These spots are scent glands used to attract females.

-Female No scent glands: Females lack the black spots on their hind wings.

The thickness of the wing ribs:

-Male: Has thinner black wing ribs.

-Female: Has thicker and darker wing ribs, giving them a more prominent pattern.

‍

‍