18S and ITS2 gut content metabarcoding of specialized feeders is not a replacement for environmental DNA assays of their reef environment

We compared multi-assay metabarcoding sequences of environmental DNA (eDNA) isolated from seawater and partially digested gut items from an obligate corallivore butterflyfish (Chaetodon lunulatus) resident at coral reef sites in the South China Sea. We specifically tested the proportional and statistical overlap of the different approaches (seawater versus gut content metabarcoding) in characterizing eukaryotic community composition on coral reefs based on 18S rRNA and ITS2 rRNA sequence data.

本研究对分离自南海珊瑚礁海域海水的环境DNA（eDNA），以及栖息于该海域珊瑚礁位点的专性食珊瑚蝴蝶鱼——新月蝴蝶鱼（Chaetodon lunulatus）的部分消化肠道内容物，开展了多检测元条形码（metabarcoding）测序，并对比了两组样本的测序结果。本研究基于18S rRNA与ITS2 rRNA序列数据，专门检验了两种实验方法（海水元条形码测序与肠道内容物元条形码测序）在表征珊瑚礁真核生物群落组成时的比例重叠度与统计重叠度。