Taxonomic Study On Platycnemididae Of China (Odonata:Zygoptera)

There are 43 genera and 428 species of Platycnemididae in the world. The taxonomy of Platycnemididae was systematically studied from China in this dissertation. Firstly, the recorded taxa of Platycnemididae were ordered systematically, and redescribed and revised by the specimens and literatures. Then, partial species of Platycnemididae(19 species) were studied based on COI gene, and Drepanosticta rufostigma, which belongs to Platystictidae, was sequenced as outgroup. We analyzed sequences and reconstructed phylogenetic trees by Neighbor-Joining(NJ), Minimum Evolution(ME) and Maximum Parsimony(MP) methods based on Clustalx1.8 and MEGA5.0 softwares. Some kinds of ownership problems were discussed combined with traditional morphological characteristics and molecular phylogenic study. The results are showed as follows:1, 35 species of Platycnemididae belong to 4 genera of 2 subfamilies are recorded from China. There ara 2 genera in Calicnemidinae: there ara 11 species in Calicnemia and 17 species in Coeliccia. There ara 2 genera in Platycnemidinae: there ara 5 species in Copera and 2 species in Platycnemis. Two new species are described: Coeliccia sichuanensis sp.nov. and Coeliccia henanensis sp.nov..2, The Indocnemis is the synonym of Coeliccia based on the morphological and molecular data.3, The mitochondrial COI gene sequences(657bp,without outgroup)of 19 species on Platycnemididae show a stong A/T bias.The average content of A, T, G and C are 30.7%, 35.6%, 17.3% and 16.4%, respectively. A+T content is 66.3%, while C+G% content is 33.7%. The average contents of A+T are different in three positions: the first is highest, the third is less and the second is least. These sequences code 219 amino acids and contein 20 kinds of amino acids. The content of Ser is highest, followed by Ile and Asn. The composition of amino acids showed a certain bias.4,Ratio of transition to transversion of COI gene sequence is 1.078 to the 15 species. Ts is slightly higher than Tv. There is has a high ratio both Ts and Tv in the first position, Ts occurred between T and C mostly, while Tv occured between T and A mostly.5,The results showed that diffent methods could consistent phylogenic trees. The relationship of the 4 genera is:(Platycnemis,(Copera,(Calicnemis, Coeliccia))). 6,The barcoding technology of COI is feasible in the classification and identification of Platycnemididae. ME method is simple and rapid.