Chromosomal Characteristics of Oxygyne shinzatoi (Burmanniaceae), and its Phylogenetic Significance

摘要

The chromosome characteristics of Oxygyne shinzatoi, subtribe Oxygyninae, tribe Thismieae, Burmanniaceae, are described and the phylogenetic significance of this species is discussed. The chromosome number of O. shinzatoi is In = 18, and the basic chromosome number is thought to be x = 9. This differs from the x = 6 of Thismia, subtribe Thisminae, tribe Thismieae, and the x — 6 or 8 of Burmannia, tribe Burmannieae. The sizes of O. shinzatoi and of T. abei chromosomes differ from those ofBurmannia. The interphase nucleus of O. shinzatoi is of the complex chromocenter type, in contrast to that of T. abei. This result suggests that there are large differences karyomorphologically between the subtribes Thisminae and Oxygyninae.