Endangered Resources Program Species Information
Red-disked Alpine (Erebia discoidalis)

Red-disked Alpine Photo by Mike Reese. Check the photos tab for additional photos.
Photo © Mike Reese

Overview

Species Overview

Red-disked alpine ( Erebia discoidalis ), a State Special Concern butterfly, has been found in large, open sphagnum-wiregrass (Carex oligosperma) bogs with scattered, stunted black spruce, cottongrass (Eriophorum spp.), and Ericads in Wisconsin. Several sites also support extensive bog birch (Betula pumila), though there is evidence that dry habitats may also support the species. Adults fly mid May through the first week of June in Wisconsin.

Status and NHI Documented Occurrences in Wisconsin

The table below provides information about the protected status (State and Federal Status) and the rank (S and G Ranks) for Red-disked Alpine (Erebia discoidalis). See the Working List Key for more information about the abbreviations used. Counties shaded blue have documented occurrences for this species in the Wisconsin Natural Heritage Inventory database. For invertebrates, dots depict locations from the "Invertebrate Atlas," a database with occurrences of rare and common aquatic and select terrestrial invertebrate species found in Wisconsin and adjacent areas. While the invertebrate atlas is a quality assured database, not all records have been verified. The map is provided as a general reference of where this species has been found to date and is not meant as a range map.

Summary Information
State Status:	SC/N
Federal Status in Wisconsin:	none
State Rank:	S2
Global Rank:	G5
Tracked by NHI:	Y
Species of Greatest Conservation Need:	Y

Documented locations of Erebia discoidalis in the Natural Heritage Inventory Database as of April 2009.

Detailed Information

Identification: Wings are blackish-brown with a large chestnut patch on forewing, visible above and below. The hindwing below is mottled and has gray shading toward the outer edge. No eyespots. The chestnut patch on the forewing is distinctive. Wingspan: 39-42mm. Length of forewing: 21-23 mm. Early stage larvae are green with light lines (Nielsen 1999).

Similar Species: None in Wisconsin.

Habitat: Large, open sphagnum-wiregrass (Carex oligosperma) bogs with scattered, stunted black spruce, cottongrass (Eriophorum spp.), and Ericads in Wisconsin. Several sites also support extensive bog birch (Betula pumila) (Nekola 1996), though there is evidence that dry habitats may also support the species. The earliest habitat report from the state is from Forest County and described as "open grassy meadows with conifers, willows, and mixed hardwoods nearby" (Elder 1961). In Manitoba, moist prairie, dry meadows and sandy ridges in jack pine forests are reported (Layberry 1998) and Michigan lepidopterists have recently found a breeding population in pine barrens (Perkins 2003).

Nectar Source: Recorded nectaring on bog rosemary (Andromeda glaucophylla) in UP Michigan (Perkins 2003). May also be attracted to plant sap and areas of damp soil with nutrients or salts (Borkin pers. comm.).

Host Plant: Probably grasses (Poa spp.) or sedges (Cyperacea). In captivity, larvae have been reared on Poa canbyi in Manitoba (Layberry et al. 1998); P. alpina, P. glauca (Scott 1986), and possibly a small sedge in western Quebec (Lessard in Layberry et al. 1998). Only Poa glauca occurs in Wisconsin. In Michigan, the natural host plant is unknown (Nielsen 1999).

Associated Species: Frieja fritillary (Boloria freija) and reported flying with Jutta Arctic (Oeneis chryxus) in Michigan pine barrens (Perkins 2003).

State Distribution: Uncommon and very localized. Ashland, Douglas, Forest, Iron, Langlade, Lincoln, Oneida, Price, and Vilas counties.

Global Distribution: Holarctic. North America from Alaska south and east to southern Alberta, northern Montana, northern Wisconsin, northern Michigan, and southern Quebec.

Threats: Unknown.

Phenology: Adults fly mid May through the first week of June in Wisconsin. May 10 is an early record of a fresh female from Forest County.

Life History: Probably a one-year life cycle in Wisconsin, though it is biennial farther north. Larvae spin flimsy cocoons in which to pupate.

Survey Guidance: Flight is slow, weak and near the ground. They avoid hot, sunny periods and stay near the trees except in the early morning and late afternoon when they move out into the open, grassy areas (Masters 1970). They will alight in the groundcover or when alarmed, will fly up and allow the wind to blow them away. Nielson (1999) notes that adults have been attracted to bait traps. Breeding has been observed in the late afternoon. New county records should be documented with voucher specimens.

Inventory, Monitoring and Research Needs: Locate additional populations. A considerable amount of potential habitat in Wisconsin has not been surveyed. There are likely a significant number of undiscovered populations throughout northern Wisconsin.

Information originally presented as part of the Online Field Guide to Rare Lepidoptera: Bogs and Barrens.

Photos

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