Synonyms and other taxonomic changes
Speyeria Scudder 1872. type species: Papilio idalia Drury
Semnopsyche Scudder, 1875. TS: Papilio diana Cramer
Mesoacidalia Reuss, 1926. TS: Papilio aglaja Linnaeus
Neoacidalia Reuss, 1926. TS: Papilio cybele Fabricius
Proacidalia Reuss, 1926. TS: Argynnis clara Blanchard
Also, the following should perhaps be (and sometimes are) included in Speyeria, but are most often considered as synonyms under a separate genus - Fabriciana. All of the species concerned are Eurasian, so the debate is not particularly relevant in North America.
Fabriciana Reuss, 1920. TS: Papilio niobe Linnaeus
Prodryas Reuss, 1926; (preoccupied Prodryas Scudder, 1878). TS: Argynnis kamala Moore
Profabriciana Reuss, 1926. TS: Argynnis jainadeva Moore
Protodryas Reuss, 1928; [replaces Prodryas Reuss, 1926]. TS: Argynnis kamala Moore
Historically, and often still, Speyeria and Fabriciana (and most other "Greater Fritillaries") have been included within an expansive concept of the closely related Eurasian genus Argynnis.
Numbers
Nearctica.com lists 14 North American species.
Most often 3 Eurasian species are also included (or 4, when S. clara & S. claudia are split).
If included, Fabriciana adds about 11 additional Eurasian species.
Identification
This distinctive genus is unlikely to be confused with any other in North America. These are medium to large sized, broad-winged butterflies (most are over 2 inches in wing span, all at least nearly this large, and many species are much larger). Most have a distinctive pattern of black dashes and spots above and with rounded or oval (usually silvered) pale spots below, particularly on the hind wing. There are a few species which diverge from the usual orange ground color, and several in which light spots below may be unsilvered. In S. diana the pattern and coloring are highly modified, but this species is so very distinctive as to be recognizable at a glance.
Only one genus in north America is closely similar enough to be confused; However, (
Boloria is composed of much smaller species, which mostly have unsilvered pale spots below that are not rounded (
B. selene & B eunomia are most like
Speyeria in coloring, but are never very much over an inch in wing span).
The genus
Euptoieta does not have a pattern of rounded white spots below, but rather a blended camouflage pattern of stripes and lines, and the wings are proportionately longer and narrower. It is also a genus of multi-brooded species, mostly favoring warmer lower or more southerly regions, and not so much the northern and high elevation regions favored by
Speyeria and
Boloria (though sometimes they fly together).
Checkerspots can be confused with Fritillaries too (and are also called "Fritillaries" by the British), but they are also much smaller than
Speyeria, and the pattern below is always distinctly different (see photos under tribe
Melitaeini). The upper side does not have a row of rounded spots near the outer edge of both the front and hind wings as do the "true" Fritillaries.
Range
Cool temperate and boreal regions of North America and Eurasia. [Some authors recognize only American species as belonging to the genus.]
Season
One brood, mostly from mid-June to mid-September.
Food
Caterpillar food plants are Violets,
Viola species.
Adults feed mostly on nectar and are avid visitors of flowers. They often gather in numbers on Composites (family Asteraceae). Occasionally they may visit moist mineral rich ground as well.
Life Cycle
Oviposition is in summer to autumn (varying with the species), mostly in grassy areas near or on Violet plants. Larvae hatch not long after and overwinter in the 1st instar usually without feeding. Caterpillars begin feeding in late winter or spring on the growing food plant and mature quickly. There have been anecdotal reports of eggs overwintering, but this is not verified by rearing studies.
Print References
Dunford, James C. Taxonomic overview of the greater fritillary genus Speyeria Scudder and the atlantis - hesperis species complexes, with species accounts, type images, and relevant literature (Lepidoptera: Nymphalidae). Insecta Mundi 0090, Sept. 2009.
Internet References
Speyeria at
Markku Savala's site "Lepidoptera and some other Life Forms"
Fabriciana at
Markku Savala's site "Lepidoptera and some other Life Forms"