Barcode of nuclear ribosomal internal transcribed spacer regions (ITS) as a useful tool to recognize a newly naturalized and potentially invasive weed, Chloris pilosa Schumach. (Poaceae), in Taiwan

An unknown grass was found naturalized in central Taiwan recently. We tried to identify it based on its morphological characters and could recognize it as a taxon of grass genus Chloris. Nevertheless it is obviously different from the other species of the genus which have been reported to occur in Taiwan. Based on its nuclear ribosomal internal transcribed spacer (ITS) sequence, through the approaches of BLAST, phylogeny reconstruction and statistic tests for alternative topologies of phylogeny, we could make sure of its identity further and recognize it as the species Chloris pilosa Schumach. precisely. The species is native to equatorial Africa and this is the first report about its occurrence in Asia. A key to the species of genus Chloris in Taiwan, morphological description and illustrations of C. pilosa are also provided in this article.