Abstract: This paper reports chromosome number and karyotype analysis of Cycas panzhihuaensis endemic to China. The material was collected from Dukou, Sichuan. It is a diploid species, with 2n=22=2m+4sm+4st+l2t. The karyotype of Cycas panzhihuaensis is different from that of the other species of the genus Cycas, which was known to be 2n=4m+8st+10t. The former is a new karyotype in the genus. The authors briefly discuss karyotype evolution of the genus Cycas in this papar.

Key words: Cycas panzhihuaensis, Karyotype