2015 Volume 18 Issue 1-2 Pages 3-8
Cytotaxonomical studies were conducted on Pilea brevicornuta Hayata in the Ryukyu Islands and Taiwan. Karyomorphology of dwarf and creeping individuals growing in riparian habitat of Amami-Oshima Island, which is morphologically distinct from normal individu-als growing in forest floor, is the main focus of this re -port. All of the studied individuals of P. brevicornuta including dwarf ones had same chromosome number of 2n = 24. The karyotype formula is 2n = 24 = 6m + 13sm + 5st for normal individual and 2n = 24 = 6m + 12sm + 6st for dwarf individual. The chromosomes of P. brevicornuta were all small with sizes varying between 0.9 and 3.0 μm. Considering the basic chromosome number in the genus Pilea, 2n = 24 is regarded as diploid based on x = 12. Despite the high variability in morphology, P. brevicornuta had remarkably uniform karyomorphology.
