1. Longest leaves (5.5–) 6–9 mm long, spreading or even ±reflexed, usually at least obscurely toothed near the apex.
1. Longest leaves 4.3–5.5 (–6) mm long, all but the lowest ascending, usually entire.
All species found in Spinulum
MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. August 23, 2019. https://www.michiganflora.net/genus.aspx?id=Spinulum.