Abstract: Tapiscia sinensis, an endemic and rare tree under protection in China, takes 17 months to complete the cycle from floral primordium initiation to fruit maturation. The morphological and anatomical changes of flower and fruit in T. sinensis were investigated in this research. The flower blossoms in late May, and is fertilized in early June. Then the zygote immediately goes into dormancy before any cell division, and this status is maintained until next March. The dormant young fruit has several characters adapted to winter survival, such as cork layer formed on ovary surface and receptacle enclosing the fruit stalk etc. The fruit does not start developing until next April. Afterward it enlarges rapidly and completes its maturation by the end of September. Its extreme long sexual reproductive cycle is due to the zygote dormancy. Therefore the fruit of the preceding year and the flower of this year appear on the same branch in the summer. The dormancy of zygote and fruit maturation in the second year in T. sinensis supports the hypothesis that Tapiscia should be raised to family level. The unique reproductive feature and other characters of systematic value suggest that the systematic position of this genus requires further study.

Key words: dormancy, fruit, Tapiscia sinensis, zygote