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Phyciodes pulchella Hübner, [1819]
Crescents; Field Crescent
Family: Nymphalidae (Brushfoots)
Species account authors: Crispin Guppy and Jon Shepard.
Extracted from Butterflies of British Columbia.
Introduction to the Lepidoptera of BC
Introduction to the Butterflies of BC
The Families of Lepidoptera of BC

Photograph

© Norbert Kondla     (Photo ID #6206)

Map

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Distribution of Phyciodes pulchella 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

Where the Field Crescent is sympatric with the Pearl Crescent, it is sometimes confused with the latter, especially females. The male Field Crescent lacks a purple flush on the margin of the ventral hindwing, and the crescent is the same colour as the ground colour of the Tawny Crescent. Both sexes have much more black in the median region of the dorsal hindwings than the Pearl Crescent.

Immature Stages

The larvae are a darker brown than the two preceding species of aster-feeders. Emmel and Emmel (1973) describe the mature larva as black with numerous branching spines. There is a dorso-lateral greyish white band, and a yellowish brown band below the spiracles.

Subspecies

BC populations are the nominate subspecies, P.p. pratensis (Behr, 1863) (TL: San Francisco, CA). Scott (1994) attempted to separate the southwestern YT and adjacent AK populations into a separate subspecies, but was apparently unaware that the species occurs continuously south from southwestern Yukon with no known distinct break that would justify setting up a separate subspecies.

Genus Description


The name Phyciodes may come from the Greek phykos (painted or "covered with cosmetics"), in reference to the complex ventral wing pattern. The common name "crescents" (Gosse 1840) refers to the crescent-shaped spot in the centre of the ventral hindwing margin.

Phyciodes in the limited sense used here is separated from the Neotropical genera Anthanassa Scudder and Eresis Boisduval by the presence of two to four in-curved hooks on the posterior tip of the tegumen of the male genitalia. The saccus is present in the male genitalia. The genus is Nearctic and contains nine species. The larvae of BC species feed on asters (Aster) or thistles (Cirsium).

Biology


Adults fly from late May to early August, depending on elevation and latitude, but there is only one generation per year. The seasonal bar graph clearly shows one peak in flight in early July. Cockle reared the Field Crescent on Aster sp. in the Kootenays (Harvey 1908). Elsewhere it has been reared from a variety of asters. The eggs are laid in a cluster on the foodplant.

Habitat


The Field Crescent is found throughout BC east of the Coast Ranges. West of the Coast Ranges and the Cascades, it is known only from southeastern Vancouver Island, with the only known extant population being in the Nanaimo River estuary, and from the adjacent mainland.

Distribution

Distribution

The Field Crescent occurs from eastern AK south through BC and the Rockies of AB to CA, AZ, and NM.

Status Information

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



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