Abstract：To investigate the phylogenetic relationships in the Lutjanus species, the partial sequences of 16 S rRNA and COⅠ genes of 12 Lutjanus species distributed in the South China Sea were amplified and sequenced. Combining the sequences of Lutjanus carponotatus, Lutjanus kasmira, Lutjanus gibbus and Lutjanus monostigma obtained from GenBank, the genetic distances were calculated, and the molecular phylogenetic trees were constructed using MEGA5.0 software. The results showed that the length of 16 S rRNA gene was 560 bp, and COⅠ gene was 639 bp. The sequence of 16 S rRNA gene was relatively conservative compared with COⅠ gene. The average inter-species genetic distances of 16 S rRNA gene and COⅠ gene were 0.039 and 0.146, respectively. Sixteen Lutjanus species were mainly divided into 4 branches in the molecular phylogenetic tree; moreover, the phylogenetic relationships in each branch showed a certain correlation with their morphological characteristics. There were several black spots on the upper back of Lutjanus russellii, Lutjanus fulviflamma and Lutjanus monostigma in the branch Ⅰ. In the branch Ⅱ, several longitudinal stripes can be observed in Lutjanus fulvus and Lutjanus kasmira, and some white spots exhibited can be observed on the upper back of Lutjanus rivalatus and Lutjanus stellatus. A large size was observed in Lutjanus sebae, Lutjanus erythropterus, Lutjanus malabaricus and Lutjanus gibbus in the branch IV; moreover the adult body colors of these fishes were bright red. In addition, Lutjanus species in branch Ⅰ exhibited a longer body size; however, the fishes showed a higher size in the branch Ⅳ. The body sizes in the branch Ⅱ and Ⅲ were between these observed in the branch Ⅰ and Ⅳ. Our results were consistent with previous studies, which suggested that the body size, coloration and band could be used as the basic classification characteristics of Lutjanus species.
2020, Vol. 33 
