Bug FAQUnsilvered Fritillary
Speyeria adiaste · Order: Lepidoptera · Family: Nymphalidae
Also called: Adiaste Fritillary
The Unsilvered Fritillary has a wingspan of about 5 to 6 cm. Males show a reddish-tan to bright brick-red upper wing surface, while the hindwing spots are unsilvered and blend with the background. It lives in coastal mountain areas of California, occurring in two separate county clusters.
Source: Wikipedia
How to recognize it
Male butterflies range from pale reddish-tan to bright brick red on the upper side of the wings. The hindwing spots lack silver and only faintly contrast with the wing color.
Source: Wikipedia
Size
The wingspan measures between 50 and 61 mm.
Source: Wikipedia
Where it lives
It is found in the coastal mountains of California.
Source: Wikipedia
What it eats
Adult butterflies sip nectar from flowers. Caterpillars feed on violet species, including Viola quercetorum.
Source: Wikipedia
Where it comes from
Populations exist in two groups: one in San Mateo, Santa Cruz, and Santa Clara counties, and another in Los Angeles, Kern, and Santa Barbara counties.
Source: Wikipedia
Where it is found in the US
Recorded in 3 of 51 states and DC. Most records: California, Washington, Wyoming.
Darker = more records. Counts are museum and citizen-science records, not population size.
Source: GBIF
Months it is reported in the US
Source: GBIF
More photos
Questions people ask
What plants do the larvae of Unsilvered Fritillary use?
The larvae eat violet plants such as Viola quercetorum.
Source: Wikipedia
Where can I find Unsilvered Fritillary butterflies?
They live in coastal mountain regions of California, especially in two county clusters: San Mateo, Santa Cruz, Santa Clara and Los Angeles, Kern, Santa Barbara.
Source: Wikipedia
Same family (Nymphalidae)
Sources
- Wikipedia: https://en.wikipedia.org/wiki/Speyeria_adiaste
Look it up elsewhere: GBIF · iNaturalist · BugGuide · ITIS · Wikipedia
Text written 2026-10-27 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-27.