Cleistogamous flowers occur at least at the lower nodes and often have only 3 or 4 short calyx lobes, whereas on the showy deep blue flowers, both calyx and corolla have 5 long lobes. The capsules open by neat little elliptic pores, one on the side of each locule.
All species found in Triodanis
MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. August 21, 2019. https://michiganflora.net/genus.aspx?id=Triodanis.