Fritillaries belong to the very large worldwide family Nymphalidae, the Brushfoots. All fritillaries have a similar appearance dorsally, tawny-orange to carrot-orange with a complex pattern of black lines and dashes. The lesser fritillaries, in the genus Boloria, are smaller than their “greater” relatives and have white or yellow ventral hindwing spots (silvered in one species) which are usually not oval in shape, or if oval are clustered and touching. Guppy & Shepard (Butterflies of BC, 2001) placed astarte as a subspecies of the holarctic Clossiana tritonia, but Pyle (Butterflies of Cascadia, 2002) resumed its current status.

Only two of our lesser fritillaries are widespread and easily found in Washington while the other four are localized to rare. Boloria astarte is one of our rarest species, found only in the far North Cascades of Washington, and north into British Columbia. Beyond Washington this species enters the US only in Glacier Park, Montana, and also flies in Alberta, Yukon, Alaska and Russia. This fritillary is found in high alpine habitats where it flies over rocky scree slopes where its host plant grows. The only known larval host in our area is Saxifraga bronchialis (Spotted Saxifrage), a species found only on high alpine slopes and ridges. This is a low-growing cushion plant with tiny, spiny succulent leaves and small white flowers on 3-inch purple stalks; it also hosts the Arctic Blue in the same habitats. Saxifraga tricuspidata (Three-toothed Saxifrage) is another probable host further north. Boloria astarte is a biennial species, flying only on alternate (even numbered) years.

The immatures of B. astarte overwinter two times before reaching maturity. According to Guppy & Shepard the first winter is spent as first instar larvae, which continue development during the 2^nd summer to fourth instars; after another winter in this stage the larvae grow to 5^th instar, pupate and eclose to adults during the third summer. In our rearing we found a considerably different pattern, the eggs hatching and developing to 4^th instars the first season. After one winter they grew to 5^th instar and pupated. As the adults do not fly every year this “laboratory life cycle” is not representative of what happens in nature, but is suggestive that an annual life cycle is possible under optimal conditions. The larvae are among the darkest of our brushfoots, virtually black until the final instar when white and dull gold dorsal spots ap- pear. The pupae hang upside down and are dark brown. In the North Cascades adults fly from mid July to mid August, females ovipositing in latest July. In captivity the larvae developed from egg hatch to 4^th instar in four weeks, then dia- paused. The following spring, development was very slow and pupation unpredictable, but a few did eventually pupate when temporarily placed in a cool place.

On the dorsal surface B. astarte is more tawny, less bright orange than our other fritillaries. Ventrally the pattern is distinctive, with an irregular angular white spot-band across the middle of the ventral hindwing. The most similar species is B. chariclea (Arctic Fritillary), which is much brighter orange dorsally; also on the ventral hindwing the angular spot band is infused with orange and is less distinct than in B. astarte. Males begin flight before females, relentlessly cruising the steep alpine slopes in search of mates. Females are more subtle, often perching inconspicuously on large boulders but nectaring readily on flowers, especially on the bright yellow Arnica. Late in the flight period most adults will be females.

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