Anchusa
Both of our species are natives of Eurasia, spreading either as weeds or rare escapes from cultivation.
1. Calyx cleft nearly to the base, the lobes at least 7 mm long and narrowly linear-attenuate.
1. Calyx cleft about half to 2/3 to the base, the lobes ca. 2-5 mm long and narrowly lanceolate to triangular.
Citation:
MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. April 3, 2025
https://mifloradev.lsa.umich.edu/flora-demo/#/genus/Anchusa