Sexual dimorphism occurs when members of the same species exhibit different coloration based on their sex. The field marks of sexual dimorphism in many Skippers are less obvious than other species like some of the Coppers.
Which of the photos below most likely shows a female Northern Broken Dash?
The butterfly on the left is most likely to be a female Northern Broken Dash. While sexual dimorphism in butterflies is less obvious than birds, some butterflies still follow the rule that colorful males attract more mates. The male on the right has more extensive and brighter orange coloration on his upperside wings, while the female on the left lacks any distinguishing orange. Females can have some dull orange/brown on the costa or upper edge of the forewing but it is not as prominent as that of the male. The male also has a rectangular spot on their upperside forewing, which caps a two-part stigma (not very visible from this picture).
Photo credits
Northern Broken Dash (female) by pinemartyn (iNaturalist)
Northern Broken Dash (male) by Kent McFarland (iNaturalist)
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