RESUMEN
ABSTRACT Pandan (Pandanus sp), Rotan (Calamus sp), and Rengas (Gluta sp) are the three most important plants growing at Kajuik Lake, Langgam, Riau Province, Indonesia; however, their species names have not been identified. This study aimed to identify their species names using nuclear internal transcribed spacer (ITS) and psbA-trnH intergenic spacer sequences. The method employed was DNA isolation from fresh leaves, PCR using primer pairs of ITS region for Pandanus sp and psbA-trnH intergenic spacer for Calamus sp and Gluta sp, electrophoresis, sequencing, and data analysis using BLASTn program and MEGA software version 6.0. Pandanus tectorius was the only one accession that was similar to Pandanus sp with the identity was 90%, however the query cover was too small, only 39%. On the contrary, Calamus sp showed the highest genetic similarity to Calamus travancoricus, but in fact, both were differed morphologically. There was no database of psbA-trnH intergenic spacer sequence available for species in Gluta. In conclusion, the species names for those plants still could not be determined. It because they might be the identified plants but their sequences databases were not available in large quantities or they were new species which had never been identified and published in public database.