SOROS, CONNIE L.* and DONALD H. LES. Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT, 06269-3043; Department of Botany, University of Guelph, Guelph, ON, Canada, N1G 2W1. - Phylogenetic relationships in the Alismataceae.
A phylogenetic analysis of Alismataceae was conducted using data from
the internal transcribed spacers (ITS-1;2) of the nuclear ribosomal
genes, the chloroplast gene rbcL, the flanking introns and
coding region of the chloroplast matK gene and morphology. The
aquatic, monocotyledonous Alismataceae consists of 13 genera which are
similar in habitat, pollination and morphology. Numerous convergences
and reduced vegetative and reproductive structures make it difficult
to interpret morphological characters for phylogenetic analysis. Our
combined data set showed high congruency with results published
previously using rbcL data alone. The combined molecular data
consistently show a monophyletic origin for the family. Other results
include a sister group relationship of Limnocharitaceae and
Alismataceae, a polyphyletic origin for the genus Echinodorus and
several well-supported monophyletic clades within the family.
Key words: Alismataceae, ITS, matk, morphology, phylogeny, rbcL, systematics