Mitochondrial cytochrome b genes of about 450 bp fragments from 3 proturan species, 5 collembolan species and 2 dipluran species have been sequenced. The number of nucleotide substitutions and Kimura 2-parameter dista...Mitochondrial cytochrome b genes of about 450 bp fragments from 3 proturan species, 5 collembolan species and 2 dipluran species have been sequenced. The number of nucleotide substitutions and Kimura 2-parameter distances have also been calculated, and a series of molecular phylogenetic trees reconstructed by using parsimony and distance methods.展开更多
A comparative study on the ultrastructure of the spermatozoa of 20 species of Protura belonging to 16 genera and 8 families was conducted. The most remarkable characteristics are the unexpected diversity of the sperma...A comparative study on the ultrastructure of the spermatozoa of 20 species of Protura belonging to 16 genera and 8 families was conducted. The most remarkable characteristics are the unexpected diversity of the spermatozoa, both in shape and fine structure. In general they can be grouped into two main categories: long flagellate spermatozoa and short aflagellate ones. Accordingly two sperm evolutionary lines of the spermatozoa were obtained: one trends towards the complicated acrosome structure and the increased number of axonemal doublets, and the other line is to shorten cell form and simplify sperm structure. The results indicate that the spermatozoa of Hesperentomon may be the primitive type, and the spermatozoa of Eosentomids probably represent the most evolved type. A sperm evolutionary tree was drawn according to the apomorphies of proturan spermatozoa. The phylogenetic position of Protura was also discussed.展开更多
文摘Mitochondrial cytochrome b genes of about 450 bp fragments from 3 proturan species, 5 collembolan species and 2 dipluran species have been sequenced. The number of nucleotide substitutions and Kimura 2-parameter distances have also been calculated, and a series of molecular phylogenetic trees reconstructed by using parsimony and distance methods.
基金Project supported by the National Natural Science Foundation of China.
文摘A comparative study on the ultrastructure of the spermatozoa of 20 species of Protura belonging to 16 genera and 8 families was conducted. The most remarkable characteristics are the unexpected diversity of the spermatozoa, both in shape and fine structure. In general they can be grouped into two main categories: long flagellate spermatozoa and short aflagellate ones. Accordingly two sperm evolutionary lines of the spermatozoa were obtained: one trends towards the complicated acrosome structure and the increased number of axonemal doublets, and the other line is to shorten cell form and simplify sperm structure. The results indicate that the spermatozoa of Hesperentomon may be the primitive type, and the spermatozoa of Eosentomids probably represent the most evolved type. A sperm evolutionary tree was drawn according to the apomorphies of proturan spermatozoa. The phylogenetic position of Protura was also discussed.
基金supported by the National Natural Sciences Foundation of China(30570210,30630010)Innovative Program of The Chinese Academy of Sciences(No.KSCX2-YW-Z-0930)project for the insect resources investigation of Liupan Mountain(LIR0810)
基金supported by Innovative Program of The Chinese Academy of Sciences(KSCX2-YW-Z-0930)Project for the insect investigation of Helan Mountain National Nature Reserve in Inner Mongolia
