*Correspondence:
Corresponding author. Current address: Yellow Sea Fisheries Research
Institute, Chinese Academy of Fishery Sciences, Qingdao 266071,
Shandong, China.
Corresponding author. Email:
liusf@ysfri.ac.an, ORCID:
0000-0003-3766-2932
Keywords: Tetraodontiformes, Morphological characteristics, DNA
barcoding, Species identification, synonym, Phylogeny
Abstract
Tetraodontiformes is a special group of higher teleosts, with a long and
problematic taxonomic history due to their wide distribution and species
diversity. It is a difficult task for both professionals and
nonprofessionals to accurately identify all species only according to
morphological characteristics. DNA barcoding can identify species at the
molecular level. In this study, we collected 616 specimens of
Tetraodontiformes and their DNA barcodes from the coastal waters of
China. According to the morphological characteristics, 50 species were
preliminarily identified, belonging to 23 genera, 6. Among them, DNA
barcoding analysis showed that Takifugu pseudommus andTakifugu chinensis are the synonyms of Takifugu rubripes .
And Lagocephalus wheeleri is the synonym of Lagocephalus
Spadiceus . The third important finding is that the species ofTakifugu have close genetic relationship. If T. rubripes ,T. pseudommus and T. chinensis are taken as one species,
the average interspecific genetic distance of Takifugu is 6.21
times of the average intraspecific genetic distance, which does not
reach the DNA barcode threshold of more than 10 times proposed by
Hebert. Among them, the genetic distance between T. oblongus andT. stictonotus is the largest, 0.045; And between T.
bimaculatus and T. flavidus is the smallest, only 0.013.
However, species can be clustered into separate clades in the NJ tree.
In conclusion, this study provided molecular basis for solving the
problem of confusion in the classification of Tetraodontiformes, it
found that there are synonym phenomena in the order, and provided
molecular evidence for clarifying the valid species names ofLagocephalus Spadiceus and Takifugu rubripes . The results
can provide reliable DNA barcoding information for the identification
and classification of Tetraodontiformes, and also provide technical
support for the development and utilization of puffer fish resources and
the identification of the original components of related commodities on
the aquatic product market.