| Abstract: | Karyological data are presented for 13 genera of palm subfamily Coryphoideae s.l. Chromosome numbers of 4 species and of genus Guihaia (G. argyrata, 2n = 36) are new. Apart from the prevailing chromosome number of 2n = 36, subfam. Coryphoideae s.l. shows extreme heterogeneity with respect to chromosome size and morphology, organization of constitutive heterochromatin (C-banding, fluorochrome staining), interphase nucleus structures and prophase condensation patterns. Five karyologically differing groups of genera can be distinguished (Coccothrinax-group, Guihaia, Livistona-group incl. Sabal, Phoenix, and Bismarckia). Chromosome evolution probably has gone from medium sized to very small chromosomes with an average length of less than 1.5 μm; hc-distribution from evenly distributed throughout the karyotype to accumulated in few chromosomes; from simple banding patterns to complicated ones (hc-elaboration). Karyotypes with chromosomes of continuously decreasing size, similar morphology, and uniform prophase condensation probably gave rise to almost bimodal karyotypes with non-uniform, heteropycnotic chromosomal structures. Changes in the organization of interphase nuclei are corresponding. Karyotype differentiation is compared to major evolutionary events in floral and vegetative morphology of subfam. Coryphoideae s.l. Karyologically, genera Phoenix and Bismarckia are isolated and the relations to the remaining part of the subfamily are not clear. |
