First report of Ulva shanxiensis L. Chen, J. Feng & S. L. Xie (Ulvales, Chlorophyta) - A vulnerable green macroalgae from marine habitat

Abstract

Green macroalgae Ulva shanxiensis L. Chen, J. Feng & S. L. Xie, 2015 (Ulvales, Chlorophyta) was previously known only from the type locality Shentou Spring, Shuozhou City, China. In this study eight geographical isolates of tubular Ulva were analysed from the western and southeastern Indian coast, which were suspected to be U. shanxiensis. Morphological and molecular assessments were congruent that the collected samples were U. shanxiensis. The study generated DNA sequence information of collected isolates at the following five loci: nuclear-encoded Internal Transcribed Spacer (ITS1), rDNA 18S, chloroplast-encoded Ribulose-1-5-Bisphosphate Carboxylase/Oxygenase large subunit (rbcL), ATPase beta-subunit gene (atpB) and Elongation factor-TU (tufA). In Maximum Likelihood (ML) phylograms based on 18S and tufA loci, all Indian isolates formed monophyletic clades with accessions of U. shanxiensis from China. In addition, the current study generated DNA sequence barcodes of this species at three additional loci for the first time in the world: ITS1, rbcL and atpB. In ML phylograms based on these three loci, all analysed isolates formed respective monophyletic clades, confirming the original species discovery. This report is significant in two key aspects: firstly, it documents the species presence outside of China for the first time. Secondly, it provides the first record of U. shanxiensis in a marine habitat, extending its distribution beyond the previously recognised limnetic (freshwater) environment.