SOROS, CONNIE L.1,2* and DONALD H. LES2. 1Department of Botany, University of Guelph, Guelph, ON, Canada, N1G 2W1; 2Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT, USA, 06269-3043. - Phylogenetic relationships in the Alismataceae.
The aquatic, monocotyledonous Alismataceae consists of 13 genera
similar in habitat, pollination and morphology. Numerous convergences
and reduced vegetative and reproductive structures make it difficult
to interpret morphological characters for phylogenetic analysis. 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 in
addition to morphology was used 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