LEWIS, CARL E.1*, SCOTT ZONA1, and JAVIER FRANCISCO-ORTEGA2. 1Fairchild Tropical Garden, 10901 Old Cutler Road, Coral Gables (Miami), FL 33156 USA; 2Department of Biological Sciences, University Park, Florida International University, Miami, FL 33199 USA. - Molecular systematics of the doum palms (Hyphaene) and related genera (Arecaceae tribe Borasseae).
Hyphaene is an easily recognized but poorly understood palm
genus of six or more species. Best known as conspicuous, dichotomously
branched palms of Africa, the genus is also found in Madagascar,
India, and the Arabian Peninsula. Using sequences of the nuclear genes
phosphoribulokinase (PRK) and RNA polymerase II (RPB2), we
reconstructed the phylogeny of tribe Borasseae. The tribe was strongly
supported as monophyletic, as were its two subtribes, Lataniinae and
Hyphaeneinae. The monophyly of Hyphaene was also strongly
supported, along with the sister relationship between Hyphaene
and Medemia. Fairchild Tropical Garden’s living palm collection
contains Hyphaene accessions from 24 separate localities across
the geographic range of the genus. A RAPD and AFLP study of these
accessions revealed groupings that correspond to the morphology-based
circumscriptions of Hyphaene dichotoma, Hyphaene
petersiana, and Hyphaene thebaica. However, Hyphaene
compressa and Hyphaene coriacea appear to comprise multiple
distantly related groupings of individuals and should be the focus of
further taxonomic study.
Key words: Arecaceae, Borasseae, Coryphoideae, Hyphaene, low-copy nuclear genes, Palmae