Great Spangled Fritillary

Speyeria cybele — the great spangled fritillary — is one of the largest brushfoot butterflies in North America and one of about 15 species in genus Speyeria (the 'greater' fritillaries). The species is widespread across the northern and central US and southern Canada (especially the northeastern and midwestern US, southern Canada, and the Pacific Northwest). Adults are 7-10 cm wingspan with bright orange-and-black uppersides marked by bold black checkering, and the species' diagnostic feature: brilliant METALLIC SILVER-AND-CREAM SPOT PATTERNS on the underside of the hindwings. The 'spangled' part of the common name refers to these dramatic silver spots — large irregular shiny spots that look like polished silver chips embedded in the wing surface. The metallic silver coloration is created by structural coloration (similar to the Gulf fritillary's silver spots) and flashes dramatically in flight as the butterfly raises and lowers the hindwings. The species is a flagship example of EXTREME LIFE-HISTORY MISMATCH with host plants in NA Lepidoptera. Adult females lay eggs in LATE SUMMER (August-September) NEAR — but typically NOT ON — VIOLET HOST PLANTS (Viola species). Tiny first-instar larvae hatch from the eggs in early autumn and IMMEDIATELY ENTER DIAPAUSE WITHOUT EATING — they crawl into leaf litter and curl up to overwinter through the cold months as ~2-mm-long unfed first-instar caterpillars. The diapause-without-feeding strategy is RARE among NA butterflies (most NA butterfly larvae feed substantially before overwintering or skip overwintering entirely) and is the species' most-cited unusual life-history feature. In SPRING (April-May), the diapaused first-instar larvae emerge from leaf litter, locate violet host plants by chemical cues, and begin feeding on the violet leaves — completing development through the second through fifth instars over 6-8 weeks before pupating in early summer. Adults emerge in mid-summer (June-July) and live 4-6 weeks as nectar feeders on a wide range of summer flowers (especially milkweed, butterfly bush, Joe-pye weed, and thistles). Larvae feed exclusively on violet (Viola) leaves — making the species a flagship example of the violet-fritillary specialist relationship in NA Lepidoptera (other Speyeria species share the same violet-only diet specialization). The species is harmless to humans and a major beneficial pollinator of summer wildflowers.