Molecular Phylogeny of Dipetrocarpaceae in Southeast Asia Based on Nucleotide Sequences ofmatK,trnL Intron, andtrnL-trnF Intergenic Spacer Region in Chloroplast DNA

To obtain a refined molecular phylogeny of dipterocarp species in Southeast Asia, nucleotide sequences ofmatK, the intron oftrnL, and intergenic spacer region betweentrnL andtrnF in chloroplast DNA were determined in 16 species throughout 10 genera. In the resultant trees Southeast Asian dipterocarp species were divided into two clusters. One cluster consisted ofAnisoptera, Vatica, Cotylelobium,andUpuna,all with the base chromosome number ofx= 11. The second cluster consisted ofHopea, Shorea, Neobalanocarpus, Dryobalanops, Parashorea,andDipterocarpus,mostly with the base chromosome number ofx= 7.Dipterocarpuswas the only genus that had the base chromosome numberx= 11 in the latter cluster. This result suggests that the chromosome number changed fromx= 11 tox= 7 afterDipterocarpusbranched in the latter cluster. Other evolutionary changes of morphological characters are also discussed.