''Speyeria adiaste'', the unsilvered fritillary or adiaste fritillary, is a species of

butterfly Butterflies are winged insects from the lepidopteran superfamily Papilionoidea, characterized by large, often brightly coloured wings that often fold together when at rest, and a conspicuous, fluttering flight. The oldest butterfly fossi ...

of the family

Nymphalidae The Nymphalidae are the largest family of butterflies, with more than 6,000 species distributed throughout most of the world. Belonging to the superfamily Papilionoidea, they are usually medium-sized to large butterflies. Most species ha ...

. It is found in coastal Californian mountains in two clusters, one in

San Mateo County San Mateo County ( ), officially the County of San Mateo, is a county (United States), county located in the U.S. state of California. As of the 2020 United States census, the population was 764,442. Redwood City, California, Redwood City is th ...

, Santa Cruz County, and

Santa Clara County Santa Clara County, officially the County of Santa Clara, is the sixth-most populous county in the U.S. state of California, with a population of 1,936,259 as of the 2020 census. Santa Clara County and neighboring San Benito County form the ...

and the other cluster in

Los Angeles County Los Angeles County, officially the County of Los Angeles and sometimes abbreviated as LA County, is the most populous county in the United States, with 9,663,345 residents estimated in 2023. Its population is greater than that of 40 individua ...

Kern County Kern County is a county (United States), county located in the U.S. state of California. As of the 2020 United States census, 2020 census, the population was 909,235. Its county seat is Bakersfield, California, Bakersfield. Kern County compris ...

, and

Santa Barbara County Santa Barbara County, officially the County of Santa Barbara (), is a county located in Southern California. As of the 2020 United States census, the population was 448,229. The county seat is Santa Barbara, and the largest city is Santa M ...

.Butterflies and Moths of North America
/ref> The

wingspan The wingspan (or just span) of a bird or an airplane is the distance from one wingtip to the opposite wingtip. For example, the Boeing 777–200 has a wingspan of , and a wandering albatross (''Diomedea exulans'') caught in 1965 had a wingsp ...

is 50–61 mm. Adults feed on flower nectar. The upper side of the male can range from a pale reddish tan to a bright brick red. Females are larger and paler than the males. Dark markings are scattered and small expect on the bold post median line. The underside can range from a pale yellow to a gray. The hindwing spots are unsilvered and barely contrast with the background color. The

larva A larva (; : larvae ) is a distinct juvenile form many animals undergo before metamorphosis into their next life stage. Animals with indirect development such as insects, some arachnids, amphibians, or cnidarians typically have a larval phase ...

e feed on ''

Viola The viola ( , () ) is a string instrument of the violin family, and is usually bowed when played. Violas are slightly larger than violins, and have a lower and deeper sound. Since the 18th century, it has been the middle or alto voice of the ...

'' species, including '' Viola quercetorum''.

Subspecies

*'' Speyeria adiaste adiaste'' *

† A dagger, obelisk, or obelus is a typographical mark that usually indicates a footnote if an asterisk has already been used. The symbol is also used to indicate death (of people) or extinction (of species or languages). It is one of the mo ...

'' Speyeria adiaste atossa'' *'' Speyeria adiaste clemencei''

References

adiaste Butterflies described in 1864 Butterflies of North America Taxa named by William Henry Edwards Lepidoptera of the United States {{Heliconiinae-stub