The fritillaries belong to the very large worldwide family Nymphalidae, the Brushfoots. Within Washington our fifteen species of fritillaries include the genera Argynnis (Speyeria), the greater fritillaries, and Boloria, the lesser fritillaries. But occasionally flying just beyond our borders and likely to be found here some day is a member of another genus, Euptoieta claudia, the Variegated Fritillary. This is a primarily tropical species intermediate between Argynnis and Heliconius, and is found as far south as Argentina.

In its breeding range the preferred habitat includes open sunny fields, prairies and roadsides, but E. claudia can be found everywhere except in deep forests. A variety of larval host plants are used including Viola (violet), Linum (flax), Plantago (plantain), Desmodium (beggar-ticks), Portulaca (purslane) and Passiflora (passion vine). Males patrol all day just above the ground for mates; a receptive female holds her wings mostly closed and abdomen raised slightly. The male lands behind and flutters his wings, then mating occurs.

In the United States E. claudia is a permanent resident from southern Arizona east to North Carolina, flying all year with multiple generations. Highly migratory and opportunistic E. claudia ranges far to the north in summer, reaching southeastern BC and across Canada to the Atlantic. Unable to withstand freezing, northern populations die out each fall. This species has not been found in WA or OR but has been reported in BC very close to the northeast WA border, and there are records from the Idaho panhandle. During invasive years E. claudia reaches its northern limits in late summer, with records in BC from Jul 17-Sep 4.

Adults have no winter hibernation stage, passing the winter in their southern range as adults. During the summer there are at least three broods. Females lay eggs singly on stems and leaves of the host plant. Eggs hatch synchronously and young larvae feed on host leaves, grazing the mid-leaf surface half through in irregular patches and leaving translucent windows. Later instars consume whole leaves, producing large jagged holes from the middle or edges. Most feeding is nocturnal, the larvae often basking in the sun during the day. Development is rapid, as little as 19 days from egg hatch to pupation, and adults eclose 9 days later. There are 5 instars and no nests are constructed. Mature larvae make little attempt at concealment and may be aposematic. Early instars derive protection from chemical droplets on their setae (hairs), as well as concealment and nocturnal feeding, and later instars possess spines, intimidating anterior horns and a black ventral gland under the head which may emit defensive chemicals.

Dorsally the adults of E. claudia are burnt orange in color and are about the same size and fairly similar to our greater fritillaries, except their forewings are somewhat narrower. Ventrally they are very different however, entirely lacking silvered spots, nor do they have the complex white markings which typify our lesser fritillaries. Instead the ventral wings are mottled cream and brown, and have several small dark “eye spots” near the periphery.

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