Rotala rotundifolia (Buch.-Ham. ex Roxb.) KOEHNE, A NEW RECORD OF AQUATIC ALIEN FLORA IN JAVA

Abstract

Rotala is a genus of freshwater plants belonging to the family Lythraceae. During botanical surveys conducted in April, a previously unreported Rotala species was observed naturalizing in Parakan Village, Bogor Province, Java. Morphological analysis identified the species as Rotala rotundifolia, a plant native to India and temperate East Asia. This study provides the first confirmed record of R. rotundifolia in Java and integrates DNA barcoding to support morphological identification. We used the Internal Transcribed Spacer (ITS) region as a molecular marker, successfully amplifying a 826 bp nucleotide sequence. Phylogenetic analysis using the NCBI database, with Heimia apetala as an outgroup, revealed a 99.97% sequence similarity between the collected specimen and reference sequences of R. rotundifolia. The resulting phylogenetic tree firmly places the Java specimen within the R. rotundifolia clade, confirming its taxonomic identity. The discovery of R. rotundifolia as an alien and naturalized species in Java highlights the need for early detection of non-native aquatic flora, which may pose ecological risks if left unmanaged. The integration of molecular and morphological approaches enhances species identification accuracy and contributes to regional floristic documentation. This finding expands the known distribution range of R. rotundifolia and underscores the importance of combining DNA barcoding with field taxonomy in biodiversity and invasive species monitoring.