Abstract:
:The circumscription and relationships of genera within the tribe Melanthieae (29 representative taxa) were evaluated using parsimony analyses of ITS (nuclear ribosomal) and trnL-F (plastid) DNA sequence data, alone and in combination. Proposed new generic circumscriptions, strongly supported by the tree statistics and topologies in all analyses, are correlated with potential morphological synapomorphies at the proper level of universality. Based on the molecular cladograms, Stenanthium is biphyletic, and the traditional Zigadenus s.l. (sensu lato) is polyphyletic. Amianthium and Schoenocaulon are distinct entities; the Veratrum complex is conservatively treated as one large monophyletic genus (including Melanthium). Although some generic relationships are not highly resolved, the analyses provide strong support for Zigadenus glaberrimus as sister to the rest of the tribe, and Amianthium muscitoxicum as closely related to Veratrum s.l. As a result of these analyses, seven genera (some with novel circumscription) are recognized within the tribe Melanthieae: Amianthium, Anticlea, Schoenocaulon, Stenanthium, Toxicoscordion, Veratrum, and Zigadenus.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Zomlefer WB,Williams NH,Whitten WM,Judd WSsubject
Has Abstractpub_date
2001-09-01 00:00:00pages
1657-69issue
9eissn
0002-9122issn
1537-2197pii
88/9/1657journal_volume
88pub_type
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