Toxicoscordion venenosum (S. Watson) Rydb. Toxicoscordion venenosum (S. Watson) Rydb. in Bull. Torrey Bot. Club 30: 272. 1903 sec. Govaerts 2013≡Zigadenus venenosus S. Watson in Proc. Amer. Acad. Arts 14: 279. 1879 syn. sec. Brasher 2009