Zigadenus was a polyphyletic genus once considered to belong to Liliaceae and now considered part of the Melanthiaceae. Once considered to be a North American genus with about 18 to 20 species, it has been broken apart on molecular grounds (see Zomlefer et al. 2001), supported by morphology and distribution. The former species are now found in five different genera, the four additional genera being Amianthium, Anticlea, Stenanthium, and Toxicoscordion. Only one species is left in this genus, Zigadenus glaberrimus known as the sandbog death camas. This species grows in pine bogs, savannas and sandy pine lands in the southeastern United States. Growing from thick, twisted rhizomes, it flowers mid summer to early fall and has many white to cream colored flowers in a loose panicle. Distinguishing characteristics from the other genera are the rhizome and two conspicuous glands per tepal.
Zigadenus elegans (syn. Anticlea elegans)
Zigadenus fremontii (syn. Toxicoscordion fremontii)
Zigadenus glaberrimus Michx. (syn. Helonias glaberrima (Michx.) Sims) is the only species to remain intact within the genus Zigadenus. It is native to the US in the Gulf coast states along the Southeastern coast, from Virginia south to northern Florida, and east to Texas. Thirty to seventy-five flowers top three foot tall inflorescences in mid- to late summer (July to September) in a sparsely branched loose panicle. The flowers are creamy white, star-shaped, with two conspicuous greenish glands on each tepal. The conspicuous filaments surround the stigma, nearly fused and about as long as the tepals, with pinkish-red dots at the base making a red/pink ring at the base of the flower. Grows at low elevations (below 100 meters) in pine bogs, savannas, and sandy pine lands. It grows from a dense thick rhizome, unlike Toxicoscordion (and other former members of Zigadenus) which grow from a true bulbs.
Zigadenus micranthus Eastw. var. micranthus (syn. Toxicoscordion micranthum)
Zigadenus muscaetoxicus, sometimes spelled Zigadenus muscaetoxicum, Zigadenus muscitoxicum, or Zygadenus muscaetoxicus is generally now considered to be Amianthium muscaetoxicum or Amianthium muscitoxicum.
Zigadenus venenosus (syn. Toxicoscordion venenosum)