1. Staminodium greenish or yellowish, the free apex usually distinctly broader than long; mature capsules (5–) 6–9 mm long; larger leaf blades truncate to rounded at base, never cordate.
1. Staminodium dark brown or purple (very rarely green), the free apex scarcely if at all broader than long; mature capsules 4–6 (–7) mm long; larger leaf blades often cordate.
All species found in Scrophularia
MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. May 28, 2020. https://www.michiganflora.net/genus.aspx?id=Scrophularia.