One hundred and one species of Odonata are recorded for Colorado, including 58 species of Anisoptera (of which 4 are new state records) and 43 Zygoptera (9 new state records). County records are indicated for each. Three major elements are recognized; predominantly eastern species occurring in the plains and mountain valleys east of the Rocky Mountains, Canadian Zone elements occurring principally above 2,440 m (8,000 ft) in the mountains, and Great Basin and western species occurring chiefly west of the mountains. The list is based primarily on the collections at Colorado State University and the University of Colorado, with additional records from the literature and from other collections.
Evans, Mary Alice
"Checklist of the Odonata of Colorado,"
Great Basin Naturalist: Vol. 48
, Article 15.
Available at: http://scholarsarchive.byu.edu/gbn/vol48/iss1/15