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Oeneis chryxus chryxus Hübner, [1819]
Arctics; Chryxus Arctic
Family: Nymphalidae (Brushfoots)
Species account authors: Crispin Guppy and Jon Shepard.
Extracted from Butterflies of British Columbia.
Introduction to the Butterflies of BC
The Families of Lepidoptera of BC

Photograph

© Ian Gardiner     (Photo ID #5812)

Map

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Distribution of Oeneis chryxus chryxus in British Columbia.
(Click on the map to view a larger version.)
Source: Butterflies of British Columbia by Crispin Guppy and Jon Shepard © Royal BC Museum

Species Information


Adult

Chryxus Arctics are medium-sized golden brown to tan butterflies without dark wing borders. They have one to three eyespots on the dorsal forewing, and none on the hindwing. The ventral hindwing has a well-defined dark band across the middle. A dark line crossing the ventral forewing juts out sharply towards the wing margin about one-third of the way back from the front edge of the wing. Males have a large dark stigma covering the forewing discal cell.

Immature Stages

Eggs of the nominate subspecies from Banff, AB, are barrel-shaped, with the base roundly flattened. They are broadest just below the midline, with the upper part narrowing slightly and the top flattened. There are 19 vertical ribs. Mature larvae are stout. They are thickest in the middle and have an arched back and two short tails. The colour is various shades of buff, with longitudinal stripes. Down the middle of the back is a narrow black stripe bordered on both sides with a yellow buff line. There is a dorsolateral broad black stripe, bordered above with a brown buff stripe and below with a red buff stripe with a reddish line in the centre. In sequence below that is a yellow line, a brown buff lateral line, a yellow line along the ventrolateral ridge, and finally a brown buff line. The feet and prolegs are yellow brown, and the head is yellow brown with brown stripes. In Colorado the overall colour and the stripes are lighter brown, with narrower dorsal and lateral stripes. The pupae are brown with darker patches and stripes; the top of the thorax and abdomen is light yellow brown with black spots and streaks (Edwards 1887-97).

Subspecies

The nominate subspecies, O.c. chryxus (Doubleday, [1849]); TL: Rock Lake, near Jasper, AB (Shepard 1984), occurs throughout most of mainland BC, north to the Yukon border. Subspecies coryi Dyar, 1904; TL: 59°54'N, 111°40'W near the west side of the Slave River, AB (Kondla 1995), occurs in northwestern BC, and is small and dull tan on the upperside of the wings. The underside of the hindwings is highly variable, ranging from similar to that of chryxus to light and finely flecked with grey allover. Females range from tan to brown on the upperside.

Genus Description


The name Oeneis refers to Oeneus, king of the ancient city of Calydon in western Greece, husband of Althaea and father of Meleagr and Tydeus. The name of the European genus Melanargia is derived from Meleagr, and another species of Satyrinae was derived from Tydeus. The common name "arctics" was first used by Holland (1898) in reference to the arctic and alpine distribution of many species.

Arctics are medium-sized brown or grey butterflies. They usually have eyespots on the wings. They fly rapidly and erratically over short distances, and then drop suddenly to the ground or onto a tree trunk. Arctics all have a two-year life cycle, with the young larvae hibernating the first winter and the almost mature larvae hibernating the second winter. The two-year life cycle results in many species having adults in flight only every second year, with butterflies in alternate years being greatly reduced in abundance or missing entirely in some or all areas.

Eggs are white or off-white in colour, and are conical in shape, with vertical ribs down the side. First instar larvae are thinly covered with hairs, and are tan or greenish. Mature larvae are slender and are tan or greenish with longitudinal stripes of various colours down the back and sides. They are thinly covered with hairs that are frequently reddish in colour. Pupae are roughly cylindrical and rounded, and have brown,yellow brown, and olive markings. Descriptions of the immature stages are all from outside BC, with the exception of the Great Arctic.

Larval foodplants are usually grasses and sedges. One species, the Jutta Arctic, also feeds on rushes. Eggs are laid singly on leaves of the foodplant, or nearby on dead leaves or debris. The foodplants naturally utilized in BC are not known for any species; the little information that is available is from Manitoba, Alberta, or the American Rocky Mountains.

Arctics fall into three basic ecological groups (Masters 1969): forest-dwelling species (macounii, nevadensis, jutta); prairie and steppe species (uhleri, chryxus, alberta); and arctic taiga-tundra/alpine summit species (bore, melissa, polixenes). Oeneis bore and polixenes can sometimes be difficult to identify by wing pattern alone, but the valves of the male genitalia are distinctly different. Oeneis rosovi is also difficult to distinguish from O. polixenes, but there are no genitalic differences between the two species.

Biology


Chryxus Arctics have a two-year life cycle (Scott 1992), at least in some areas. In most areas of BC they fly every year. They are in flight in June and July at low elevations, into August at high elevations. They overwinter as partly grown larvae (Edwards 1887-97). Females lay eggs on tree bark and twigs on or near the ground (Scott 1992). In open meadows, males perch on open dirt cut banks along roads, and females move in short flights through the grassy areas. In forest areas, males perch on fallen logs and branches along the forest edge in sunny patches. The larval foodplant may be Festuca idahoensis in Washington (Pyle 1981), and Carex may be used in Colorado (Scott 1992). Larval foodplants in eastern Canada are grasses such as Danthonia spicata, Oryzopsis pungens, and Phalaris arundinacea (Klassen et al. 1989).

Habitat


Chryxus Arctics are found throughout interior BC, east of the Coast Range. They inhabit dry grassland, forest openings, and dry alpine tundra.

Distribution

Distribution

Chryxus Arctics are found from southeastern AK southeast across boreal Canada, and south through mountainous areas to NM and northern CA.

Status Information

Origin StatusProvincial StatusBC List
(Red Blue List)
COSEWIC
NativeS5YellowNot Listed



BC Ministry of Environment: BC Species and Ecosystems Explorer--the authoritative source for conservation information in British Columbia.

General References