Diana….
Really……
The males have a beard.
I never thought to look for a beard, LOL!
Actually, I see that the Males have a ‘black dot’ low on their wings. And the Females have thicker and more sturdy wings with no black dot because THEY DO ALL OF THE HEAVY LIFTING! ;)
https://monarchbutterflygarden.net/female-or-male-monarch-butterfly-pictures/
OK! Fine! Force me to LEARN SOMETHING today, LOL!