Thelypteridaceae

1. Pinnae totally separated, rachis not winged; blades elongated and ± elliptic in outline.

Thelypteris

1. Pinnae connected by a narrow wing of tissue along the rachis (except between the lowermost pinnae pairs in Phegopteris connectilis); blades ± triangular.

Phegopteris

Citation:

MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. April 29, 2017. http://michiganflora.net/family.aspx?id=THELYPTERIDACEAE.