|Snijman, D - NATIONAL BOTANICAL INSTIT|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: March 1, 2003
Publication Date: April 2, 2003
Citation: Meerow, A.W., Snijman, D.A. 2003. Last time around: Multigene approaches to the phylogeny of Amaryllidaceae, and assessing its familial limits. The Third International Conference on the Comparative Biology of the Monocotyledons. Interpretive Summary: Not Applicable.
Technical Abstract: Results to date with the plastid gene rbcL and non-coding trnL-F sequences confirm the monophyly of the Amaryllidaceae s. s. as a whole, strongly support the mostly African tribe Amaryllideae as sister to the rest of the family, and resolve geographically-based monophyletic groups, but fail to resolve the relationships among several basal lineages in the family (the African Haemantheae and Cyrtantheae, the Australasian Calostemmateae, and the American and Eurasian sister clades). Preliminary data suggested that plastid ndhF might succeed in clarifying these relationships, but this does not appear to be the case. Nuclear ribosomal ITS sequences have resolved the relationships of the American genera very successfully, and have also been used at the tribal and generic levels. Within the Eurasian clade, we have encountered considerable paralogous variation for ITS, especially in the genera Leucojum and Sternbergia. We are thus in the process of refining a family-wide alignment of ITS that should provide sufficient resolution at the more basal nodes of the family tree. Above the family level, Amaryllidaceae, Agapanthaceae and Alliaceae form a well supported monophyletic group, but exact resolution of the relationships among the three subclades varies depending on the sequence matrix utilized. The Angiosperm Phylogeny Group has advocated combining all three into a single family, Alliaceae. We discuss this decision, which has historical precedent, but recommend that Amaryllidaceae be conserved as the name for the family in such a treatment.