silverspots

Definition

A group of large, orange-brown North American fritillary butterflies (genus Speyeria, family Nymphalidae) characterized by distinctive silvery or cream-colored spots on the ventral hindwings. These univoltine butterflies are strongly associated with violets (Viola spp.) as obligate larval host plants and are considered indicator species for prairie and meadow ecosystem health. The common name refers specifically to the reflective submarginal spots that serve as a key diagnostic feature separating Speyeria from superficially similar Argynnis fritillaries.

Etymology

From the silvery or metallic spots on the underside of the hindwings, a characteristic field mark visible when the wings are closed.

Example

The Oregon silverspot (Speyeria zerene hippolyta) is a federally threatened subspecies whose larvae feed exclusively on early blue violet (Viola adunca) in coastal grassland habitats.

Synonyms

• Speyeria

Related Terms

• fritillary
• Nymphalidae
• Univoltine
• host plant specificity
• Indicator species
• prairie ecosystem

Usage Notes

Used in the plural to refer collectively to species within the genus Speyeria; individual species are typically referenced with the singular 'silverspot' (e.g., 'the Atlantis silverspot'). Not to be confused with 'silver-spotted skipper' (Epargyreus clarus), a unrelated hesperiid. The term has no singular/plural distinction in vernacular usage—'silverspot' refers to one species or individual, 'silverspots' to multiple species or the group as a whole. Some authors restrict 'silverspot' to the more narrowly defined western species, while others apply it to all Speyeria.