Horace's Duskywing (Erynnis horatius) - male

12 September 2015: This is the second observation we post to iNaturalist of this particular butterfly species. Horace's Duskywing (Erynnis horatius) is considered a large skipper and can grow up to 1.5 to 2.0" across from one tip of its wings to the other. Horace’s Duskywing’s range extends throughout most of the eastern two-thirds of the United States encompassing 37 states and the District of Columbia from the Great Lakes to the Río Bravo/Río Grande (north and south) and from the Colorado River to the Atlantic Ocean (east and west) generally speaking. The western third of the nation generally does not provide a home for Horace’s Duskywing’s range but it does fly south through Texas at least into northeastern Mexico. The nationally-limited range maps we consulted online for this butterfly do not discuss the range beyond the national borders of the United States and so we fail to understand fully the extent of its range to the south of the U.S.-Mexico border. But because Horace’s Duskywing is most definitely a North American butterfly it is and has long been an original authentic resident of the Western Hemisphere. This particular observation of Horace’s Duskywing was made in one of the flower gardens at the main campus of Texas Woman’s University (TWU) in Denton, Texas.

We acknowledge and thank Dr. Cliff Ivy who is a contributing editor at BugGuide for making the positive ID of our observation of Horace’s Duskywing. That ID can be accessed online here: http://bugguide.net/node/view/1181699

Sources:

“Erynnis horatius - (Scudder and Burgess, 1870),” NatureServe Explorer: An Online Encyclopedia of Life, NatureServe, description and range map provided, accessed 1.12.16, http://explorer.natureserve.org/servlet/NatureServe?searchName=Erynnis+horatius

“Horace’s Duskywing (Erynnis horatius),” BugGuide, specimen from Dallas Arboretum, Dallas County, Texas, USA, September 7, 2015, accessed 1.12.16, http://bugguide.net/node/view/1135963/bgimage

“Horace’s Duskywing (Erynnis horaitus,” Dallas County Lepidopterists’ Society, Butterflies of Dallas County, for a digital image of the dorsal and ventral view of a specimen captured in Dallas County, Texas, accessed 1.12.16, http://www.dallasbutterflies.com/

“Horace’s Duskywing (Erynnis horatius),” Junior Wildlife Journal, New Hampshire Public Television, provides a good description of this species and a range map indicating the extent of its presence in the United States, accessed 1.12.16, http://www.nhptv.org/wild/horacesduskywing.asp

“Horace’s Duskywing (Erynnis horatius),” New Jersey Butterflies, NABA – North Jersey Butterfly Club, presents a brief description of this species, accessed 1.12.16, http://www.naba.org/chapters/nabanj/butterflies/horaces_duskywing.html