The receptacular chaff is usually quite visible as the slender bristle-like tips extend well up among or beyond the tips of the mature disk flowers.
1. Receptacle completely chaffy (all the way to the marginal disk flowers); ray flowers pistillate; involucre ca. (4–) 4.5–6 (–6.5) mm long; achenes ribbed but otherwise smooth; plant nearly or quite odorless.
1. Receptacle not chaffy around the marginal flowers of the disk; ray flowers sterile; involucre ca. 3–4.2 mm long; achenes warty-tuberculate; plant with unpleasant odor.
All species found in Anthemis
MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. January 25, 2021. https://michiganflora.net/genus.aspx?id=Anthemis.