male Mylitta crescent nectaring on tocalote
male Phyciodes mylitta mylitta nectaring on Centaurea melitensis
Asteraceae
The first crescent butterfly I became familiar with was in Ohio, the pearl crescent (Phyciodes tharos). It became my mental model of what a crescent should look like on the top, something I liken to a grandmother's lace doily (don't ask me why, it just worked for me). It was such an immediate ID clue for me that I don't think I ever really bothered to look at the underside (ventral) of the wings. It wasn't until I recently picked up Art Shapiro's Field Guide to Butterflies of the San Francisco Bay and Sacramento Valley Regions that it finally dawned on me why crescents are named such. Just look at that white crescent shape, along the margin in the middle of the ventral hindwing! Cool. Note: not all crescents have such strongly marked crescents. Also to note: female Mylitta often have more strongly marked topside (dorsal) patterns. Ah, I'm slowly getting the hang of local IDs...