The New World greater fritillaries have long been included in the genus Speyeria, however because of close similarities to European relatives they have recently been moved to the genus Argynnis, with Speyeria being reduced to sub-genus level. The greater fritillaries belong to the very large worldwide family Nymphalidae, the Brushfoots. In Washington we have nine species of greater fritillaries, all of which belong to the genus Argynnis. Most Argynnis have a similar appearance dorsally, showy tawny-orange to carrot-orange with a complex pattern of bold black lines and dashes. The greater fritillaries are generally large, and have oval spots, often silvered, on the ventral hindwing. These butterflies are fast, powerful flyers, but often pause at flowers to nectar. Thistle flowers are a favorite nectar source for A. cybele.

Our largest Cascadian fritillary, Argynnis cybele is found in many but not all mountainous and hilly areas, but is absent from the driest regions and W of the Cascades in BC. Beyond Cascadia the range includes most of southern Canada and northern USA. Preferring moist woodlands, meadows and riparian areas A. cybele occurs from sea level to 6000 ft, flying here from early June to early September. Larval hosts are violets including Viola glabella (Stream Violet), V. adunca (Blue Violet), V. nuttallii (Nuttall’s Violet) and V. sempervirens (Evergreen Violet). The female lays eggs singly and haphazardly near senesced Viola host plants.

Eggs hatch in 10-12 days, after which the larvae congregate under cover and diapause through the winter as unfed first instars. The following spring the larvae grow to a large size of nearly 2 inches, feeding nocturnally and seeking cover during the day under leaves, rocks or debris. Violet leaves are eaten from the edges inward, leaving large scooped-out holes. The larvae make no nests at any stage. Larvae L2 and older possess ventral glands which evert if the larva is threatened, emitting a musky odor. The handsome larvae are very dark, nearly all black, and have multiple rows of branched orange and black spines and the hanging pupa is dark brown with orange spines. Development from L1 to pupa takes an average of 44 days, females about a week longer then males, and adults eclose when the pupa is about 13 days old. The survival strategy is concealment (nocturnal feeding), physical protection with spines, possible chemical protection and camouflage. There are six larval instars and A. cybele is single-brooded throughout its range. The larvae of this species are most similar to those of other Argynnis, especially A. egleis, A. hydaspe and A. hesperis, all of which are also dark. Argynnis cybele has oranger spines than these three species, and only in A. cybele is the dorsal stripe completely lacking and orange patches on the larval head so strongly developed.

The Great Spangled Fritillary is the most easily identified of our greater fritillaries, this being our only Argynnis in which the male and female are clearly dimorphic (different). Dorsally the female is black (eastern WA) or dark chestnut (west), while the male is bright orange. Both dorsally and ventrally the inner 2/3 of the hindwing is dark reddish brown to black while the outer third is a broad band of contrasting pale yellowish (F) or orange (M). The ventral hindwing has widely spaced silvered spots which are dramatically smaller than in our other Argynnis species.

All Photos by Dave Nunnallee

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