Zigadenus

Star Lilies
Sandbog Deathcamas, Zigadenus glaberrimus
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Monocots
Order: Liliales
Family: Melanthiaceae
Genus: Zigadenus
Michx.
Species

See text.

Zigadenus (often misspelled "Zygadenus") is a genus of flowering plants in the family Melanthiaceae. As currently described in the research literature, it is monotypic, including only the Sandbog Deathcamas, Zigadenus glaberrimus. Until recently, the genus was considered to include a wider range of species, all known as Deathcamases or Star Lilies, and it is this circumscription of the genus that is likely to be met with in most books and websites. Before the general reorganization of flowering plant families that has taken place in recent decades (for example by the Angiosperm Phylogeny Group), Zigadenus was placed in the family Liliaceae.

Deathcamases are perennial plants growing from a bulb or rhizome. In most cases they have long narrow leaves that grow from the base of the plant. The flowers are bisexual; they have six petals and are radially symmetrical, and in the best known species are white or yellowish-white. They are found in North America, Central America, and Asia. The name "deathcamas" comes from the similarity of the plants to the camases, in the unrelated genus Camassia. Camases are an important food plant, but all the deathcamases are at least unpalatable to livestock because of alkaloids present especially in the bulbs. Some deathcamases are seriously toxic to both animals and humans, and can cause convulsions, coma, and death.

Recent phylogenetic efforts have led to the conclusion that the genus as formerly recognised was polyphyletic. The species formerly placed in it have therefore been placed into five genera which are believed to be monophyletic, Amianthium, Anticlea, Stenanthium, and Toxicoscordion, leaving only Zigadenus glaberrimus in Zigadenus. Although the reorganization was done primarily on molecular grounds, it is supported by morphological and distributional considerations.[1] [2]

There are more than twenty species in the genus as it was previously circumscribed. The list below gives the genus placements as recommended by Zomlefer and Judd (2002). Distributions and some key features of the genera are as follows:

List of species

References

  1. ^ Zomlefer, WB; NH Williams, WM Whitten, WS Judd (2001). "Generic circumscriptions and relationships in the tribe Melanthieae (Liliales, Melanthiaceae), with emphasis on Zigadenus: Evidence from ITS and TRNL-F sequence data". American Journal of Botany (Botanical Society of America) 88 (9): 1657–1669. doi:10.2307/3558411. JSTOR 3558411. PMID 21669700. 
  2. ^ Zomlefer, WB; WS Judd (2002). "Resurrection of Segregates of the Polyphyletic Genus Zigadenus s.l. (Liliales: Melanthiaceae) and Resulting New Combinations". Novon (Missouri Botanical Garden Press) 12 (2): 299–308. doi:10.2307/3392971. JSTOR 3392971. 

External links