male Montana crescent
male Phyciodes pulchella montana (formerly Phyciodes campestris montana)
If I wasn't careful, I might mistake the topside (dorsal) for a female Mylitta crescent! Technically this is a subspecies of the field crescent, but considering I won't see this anywhere near where I live, I prefer to think of it as being a different entity entirely. Our Monterey County field crescents (Phyciodes pulchella pulchella) are much darker than this, looking like a predominantly dark brown butterfly vs. an orange one.