The Grand Traverse Region of Lower Michigan is of special interest zoo- geographically in that it includes the northernmost known localities for various species of organisms characteristic of the Carolinian Biotic Province (Douglass 1977, 1983; McCann 1979).
Douglass, John F.
"Northerly-Outlying Records of Two Species of Hawkmoths (Lepidoptera: Sphingidae) in Michigan,"
The Great Lakes Entomologist: Vol. 25
, Article 8.
Available at: http://scholar.valpo.edu/tgle/vol25/iss3/8