LAUSR

Abstract Morphological identification of gastropods can be difficult considering the larva of species and high similarity among the same genera. DNA barcoding has been widely used in species identification and biodiversity research. The purpose of this study was to explore the feasibility of using the cytochrome c oxidase subunit I (COI) gene for the identification of gastropod species and to construct a reliable DNA barcoding reference database of gastropods in Hainan island, China. A total of 306 mitochondrial COI barcode sequences were obtained from 120 species, 35 families and 7 orders of gastropods. The average length of the sequence was 640 base pairs. The average genetic distances based on Kimura two parameter (K2P) within species, genera, families, orders and classes were 0.9 %, 14.7 %, 18.9 %, 24.5 % and 28.6 %, respectively. Most of the gastropod species could be identified using COI sequences. Our results confirmed that the identification method combining morphology and DNA barcode greatly improved the efficiency of species identification. In this study, we found three new record species in China, namely Semiricinula tissoti (Petit de la Saussaye, 1852), Engina alveolata (Kiener, 1836) and Wallaconchis ater (Lesson, 1831). Overall, this study revealed that the identification of gastropods by DNA barcoding is efficient, and COI sequencing technology can be used for the identification of gastropod species and thereby can be used to manage fisheries and assess biodiversity.