ARS | Publication request: PHYLOGENY AND BIOGEOGRAPHY OF CRINIUM L. (AMARYLLIDACEAE) INFERRED FROM PLASTID AND NUCLEAR NON-CODING DNA SEQUENCES

Submitted to: Botanical Journal of the Linnean Society
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: October 24, 2002
Publication Date: March 1, 2003
Citation: Meerow, A.W., Lehmiller, D.J., Clayton, J.R. 2003. Phylogeny and biogeography of Crinium l. (Amaryllidaceae) inferred from plastid and nuclear non-coding dna sequences. Botanical Journal of the Linnean Society.

Interpretive Summary: The genus Crinum is an important group of subtropical flower bulbs grown throughout the world. It is the only genus of the Amaryllis family found on every continent except Antarctica. We used two DNA sequebces to explore the relationships of Crinum species and help understand the history of the genus' spread through the tropics of the world. We determined that one species of Crinum, C. baumii, is more closely related to Ammocharis and Cybistetes than to Crinum. Three major groups are resolved in Crinum by the DNA sequences. One unites an American group with tropical and North African species. The second includes all southern African species and the Australian C. flaccidum. The third includes Madagascar, Australasian and Indoasian groups, with a few southern African species that have the same type of flower form. The salverform, radially symmetrical flowers of the historically recognized subgenus Crinum appear to have evolved several times in the genus from ancestors with bilaterally symmetrical, bell-shaped or funnel-shaped flowers (subgenus Codonocrinum), or vice versa. The origins of Crinum appear to be in southern Africa. The genus underwent three major waves of radiation corresponding to the three main groups resolved in our DNA family trees. Two entries into Australia for the genus are indicated, as are separate Indoasian and Australasian dispersal events.

Technical Abstract: The genus Crinum L. is the only pantropical genus of the Amaryllidaceae. We present phylogenetic analyses of nrDNA ITS and plastid trnL-F sequences for all continental groups of the genus Crinum and related African genera, with the genus Amaryllis used as outgroup. ITS indicates that C. baumii is more closely related to Ammocharis and Cybistetes than to Crinum sensu stricto. Three clades are resolved in Crinum s.s. One unites a monophyletic American group with tropical and North African species. The second includes all southern African species and the Australian endemic C. flaccidum. The third includes monophyletic Madagascar, Australasian and Indoasian clades, with southern African species. The trnL-F phylogeny resolves an American and an Asian/Madagscar clade, and confirms the relationship of C. flaccidum with species endemic to Southern African. The salverform, actinomorphic perianths of subg. Crinum appear to have evolved several times in the genus from ancestors with zygomorphic perianths (subg. Codonocrinum), or vice versa, thus neither subgenus is monophyletic. The origins of Crinum appear to be in southern Africa, as species from this region resolve in basal positions in all but one of the major clades in the ITS trees. The genus underwent three major waves of radiation corresponding to the three main clades resolved in our trees. Two entries into Australia for the genus are indicated, as are separate Indoasian and Australasian dispersal events.