We drove up a side road from the Rogue River just outside Galice and saw these striking moths flying along the roadside. The only one we managed to photograph was sorely bedraggled. We're thinking 8163 Platyprepia virginalis but we didn't see any spots on the hind wing though it looks like there might be some on the underside view. CBIF has an image that looks very much like ours, with all black hindwings, but listed as 8163b .