The Karyotype, Complete Sequence Of Cyt B Gene And Embryonic Development Of Hynobius Guabangshanensis

Hynobius guabangshanensis which belongs to Hynobiidae, Urodela, Amphibia, is a new species discovered by professor Shen in Qiyang County, Hunan Province. The author of the thesis has done a series of studies of the karyotype, complete sequence of Cyt b gene and embryonic development of Hynobius guabangshanensis from 2005 to 2007.Taking marrow and enteric epithelial cells as the material, this thesis studies the karyotype of Hynobius guabangshanensis firstly. The results show that the diploid number is 2n=56, and the karyotype formula is 2n=56=24M+12SM+4ST+I6m, and NF=96, among which there are 12 pairs of metacentric chromosomes, 6 pairs of submetacetic ones, 2 pairs of subtelocentric ones and 8 pairs of microchromosomes. No heteromophic chromosome has been found.In the second phrase, the author of this thesis applies PCR amplification techniques to get the full length of cytochrome b gene sequence (l142bp) of Hynobius guabangshanensis, and takes statistics on its bases with software Jellyfish. Then taking the Chinese giant salamander (Andrias davidianus) as the outgroups, together with the homologous sequences of H. formosanus, H. arisanensis, H.leechii, H. amjiensis and H. chinensis from GenBank, a molecular phylogenetic tree is constructed by the method of Neighbor-joining (NJ). The NJ tree shows that Hynobius is a monophyletic group, which could be divided into two sister groups: group Taiwan and group Mainland. H. formosanus and H. arisanensis make the Taiwan group and the other 4 species make the Mainland group. And among them guabangshanensis has the closest relationship with chinensis.The embryonic development of Hynobius guabangshanensis was examined continuously and photographed by a digital camera from January to February 2005. According to the exterior appearance and the typical characteristics, process of embryonic development can be divided into 21 periods. With the water temperature of 6.5～10℃, it takes 1134h for the fertilized eggs to hatch, and the newly hatched larvae of Hynobius guabangshanensis have an average total length of 16.50mm.