Endangered Resources Program Species Information
An Owlet Moth (Macrochilo bivittata)

Overview

Species Overview

An Owlet Moth (Macrochilo bivittata) A tan to very light brown moth, the forewing above marked with two longitudinal dark chocolate brown dashes, one along the full length of the inner margin and the other in the apical area from the midpoint toward the outer margin. The palpi are long and upturned, and the antennae pectinate in the male.

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 An Owlet Moth (Macrochilo bivittata). 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: S3 Global Rank: G3G4 Tracked by NHI: Y Species of Greatest Conservation Need: Y

Detailed Information

Identification: A tan to very light brown moth, the forewing above marked with two longitudinal dark chocolate brown dashes, one along the full length of the inner margin and the other in the apical area from the midpoint toward the outer margin. The palpi are long and upturned, and the antennae pectinate in the male. Send specimen to a specialist for identification. Immatures have not yet been described.

Similar Species: This species is distinctive in pattern.

Habitat: Wetland, especially calcareous areas of sedge meadows, fens, wet prairie. Also Great Lakes coastal wetlands and occasionally boggy areas.

Host Plant: Larvae in this subfamily feed on lichens, fungi, or dead leaves (Rings et al. 1992). This species appears closely associated with reed canary grass (Phalaris arundinacea) in New York. In Wisconsin the hostplant is probably a sedge, Carex sp.

Associated Species: Rare associates are mulberry wing (Poanes massasoit), Dion skipper (Euphys dion), and smoky eyed brown (Satyrodes eurodice) in Wisconsin.

State Distribution: Statewide: Bayfield, Burnett, Dane, Door, Forest, Green Lake, Jackson, Kenosha, Marquette, Oconto, Oneida, Ozaukee, Rusk, Shawano, Trempealeau, Waukesha and Waushara counties. In Wisconsin, this species seems to be doing well, and continues to be found in the majority of wetland sites surveyed. New county records should be documented with voucher specimens.

Global Distribution: Was widespread from New Brunswick to Manitoba and south into northern tier of US states, especially Maine. Most historic records are from Maine and Ontario, modern ones from at least Wisconsin and New York. One current site in Ohio.

Threats: Probably impacted by massive indiscriminent spraying for spruce budworm in Maine, at least formerly. Likely impacted by applications of Bt for gypsy moth control. Also, overwintering larvae are vulnerable to being killed by fires.

Phenology: Present as adults from early July to mid August in Wisconsin.

Life History: Early stages not known for any North American species of Macrochilo but were described briefly for the type species, M. cribrumalis. Its larva feeds on Carex, hibernates partly grown, finishes feeding and pupates in a fragile cocoon in May and flies as an adult from June to early August (Ferguson 1982).

Survey Guidance: Blacklight for adults from early July to mid August. It appears that the species rarely leaves or can be attracted out of its wetland habitat. Part of the success in locating it in Wisconsin likely has to do with the use of small, portable blacklight traps that are able to be set in the midst of the populations. Moths are attracted to blacklight if weather conditions permit moth activity. In general, a temperature in the low 50’s F or higher at dusk is necessary for successful sampling. Cloudy, humid conditions (even a light drizzle) with little or no moonlight are most desirable.

Inventory, Monitoring and Research Needs: Locate additional populations, particularly in sites managed by fire. It has not turned up in numerous recent calcareous wetland samples eastward, but does turn up now and then in upstate New York. In Wisconsin, this species seems to be doing well, and continues to be found in the majority of wetland sites surveyed. New county records should be documented with voucher specimens.

Additional Information: The largest number of individuals per site has been found in Great Lakes coastal wetlands.

Management Guidance: Avoid excessive burning of habitats. Divide area into several burn units, leaving at least half or more of the area unburned.

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

Photos

Click on a photo to view a larger version. Please considering donating your photos to the Endangered Resources Program for educational uses. See also information regarding use of photos

Photo © Les Ferge.

Related Links

Links to Additional An Owlet Moth Information

• Canadian Biodiversity Information Facility (CBIF) [Exit DNR]

Other Links Related to Butterflies and Moths

• Wisconsin Butterflies (Mike Reese)
• More Butterfly Links
• The Field Museum [Exit DNR]
• Online Field Guide to Rare Lepidoptera: Bogs and Barrens