Checkerspots: Gillett’s checkerspot (Euphydryas gillettii)
(Lepidoptera: Nymphalidae: Melitaeinae: Melitaeini)
Profile prepared by Mace Vaughan and Matthew Shepherd, The Xerces Society for Invertebrate Conservation
Gillett’s checkerspot is a striking and beautiful butterfly with a distinctive orange-red submarginal band across the predominately dark-brown to black wings. It may be found in a variety of damp habitats in mountains, including open, moist conifer forests, moist meadows, and streamsides. Gillett’s checkerspot is rare throughout its range (southeast British Columbia, southwest Alberta, Montana, eastern Idaho, and western Wyoming). It usually occurs as widely scattered, isolated colonies. Its habitat is prone to disturbance by grazing.
Xerces Red List Status: Vulnerable Other Rankings: Canada – Species at Risk Act: None Canada – provincial status: None Mexico: N/A USA – Endangered Species Act: None USA – state status: MT: Species of Concern NatureServe: G2G3 IUCN Red List: N/A
Gillett’s checkerspot is rare throughout its range. It usually occurs as widely scattered, isolated colonies. Its habitat is sometimes unstable and prone to disturbance by grazing. Most colonies are on unprotected land. Those that occur in National Parks, for example, may have some protection, but if grazing is allowed then they cannot be considered protected. In the state of Montana, Gillett’s checkerspot is listed as a Species of Concern.
Gillett’s checkerspot is a striking and beautiful medium sized butterfly in the family Nymphalidae (brush- footed butterflies). It has a wingspan of 38 to 48 mm. The upperside of the wings are predominately dark-brown to black (closer to the body), with a wide orange-red submarginal band and other cell-spots of red and white. The white spots appear as bands broken by dark-brown. The underside is similar, although with less dark-brown and more white spots. The orange-red submarginal band is a distinctive feature. Pyle (2002) states: “No other checkers look red-banded.”
The mature larva is dingy yellow with a lemon-yellow dorsal stripe and white lateral stripes. The spines are yellow on the back and black on the sides.
Euphydryas gillettii (Barnes), 1921.
Gillett’s checkerspot may be found in a variety of damp habitats in mountains, including open, moist conifer forests, moist meadows, and streamsides. Larval hostplants include twinberry honeysuckle (Lonicera involucrata), common snowberry (Symphoricarpos albus), and American alpinespeedwell (Veronica wormskjoldii).
There is one flight period from June to August. During this period males patrol or perch high in trees or tall vegetation searching for females. The adults are very local and remain near hostplants. Eggs are laid in groups on the underside of hostplant leaves during July. Young caterpillars aggregate in silk nests and feed on leaves and buds. They separate to complete development in spring. The length of life cycle and timing of hibernation varies with altitude. At low elevations, the life cycle is completed in a single year, with fourth instar caterpillars hibernating. At high altitudes, caterpillars need two years to complete development. In the first year they feed briefly and hibernate as early-instar caterpillars. They resume feeding in the second summer and hibernate again as fifth instars.
Very local in southeast British Columbia, southwest Alberta, Montana, eastern Idaho, and western Wyoming. There is a single population of this species in eastern Oregon.
Courtesy of Butterflies and Moths of North America, Big Sky Institute.
The biggest threat is from grazing whether by native ungulates or introduced livestock. Colonies of Gillett’s checkerspot are isolated and susceptible to extirpation by apparently small changes. Excessive grazing in one season could destroy a colony.
The important issue is to ensure an adequate abundance of larval hostplants by maintaining the vegetation at an appropriate successional stage. This may require managing grazing both of livestock and native ungulates.
All populations should be monitored to assess status.
Pyle, R. M. 2002. The Butterflies of Cascadia. A Field Guide to All the Species of Washington, Oregon, and Surrounding Territories. Seattle Audubon Society, Seattle, WA.
Scott, J. A. 1986. The Butterflies of North America. Stanford University Press, Stanford, CA.
Tilden, J. W. 1986. A Field Guide to Western Butterflies. Houghton-Mifflin Co., Boston, MA.
Big Sky Institute, Butterflies and Moths of North America: Gillett’s checkerspot (Accessed 1/21/09)
Canadian Biodiversity Information Facility; Species Bank: Gillett’s checkerspot (Accessed 5/10/05)
Nearctica; The Butterflies and Skippers of North America: Gillett’s checkerspot (Accessed 5/10/05)
NatureServe Explorer (Accessed 9/23/08)
Vaughan, D. M., and M. D. Shepherd. 2005. Species Profile: Euphydryas gillettii. In Shepherd, M. D., D. M. Vaughan, and S. H. Black (Eds). Red List of Pollinator Insects of North America. CD-ROM Version 1 (May 2005). Portland, OR: The Xerces Society for Invertebrate Conservation.