Karyomorphology and relationships of Amentotaxus Pilg.

In this paper, two species in Amentotaxus Pilg. from the mainland of China, A. argotaenia and A. yunnanensis, were karyomorphologically studied. They commonly showed the interphase nuclei of the complex chromocenter type and mitotic prophase chromosomes of the interstitial type. Their karyotypes were formulated as K(2n)=36=8m+28T, both belonging to Stebbins^ 1B type and with the N. F. value (number of fundamental) being 44. The chromosome number and karyotype of A. yunnanensis were reported here for the first time. Karyomorphological features of Amentotaxus, especially the N. F. value, together with other evidence, have indicated its close relationship with Torreya within the Taxaceae.