Title: Chromosome Studies of Native Lowland Diploid Species of Taraxacum (Asteraceae) in Japan
Abstract: Diploid lowland Taraxacum classified as T. elatum, T. hondoense, T. longeappendiculatum, T. japonicum, T, maruyamanum and T. platycarpum according to Kitamura (1957) were studied cytologically. Karyotypic formulae of the 6 forms were as follows: T. platycarpum, 2n=16=2M+10m+4mcs; T. elatum, 2n=16=12m+4mcs: T. hondoense, 2n=16=2M+10m+4mcs; T. longeappendiculatum, 2n=16=12m+4mcs; T. japonicum, 2n=16=12m+4mcs; T. maruyamanum, 2n=16=14m+2mcs. The karyotypes from T. elatum, T. hondoense, T. longeappendiculatum, T. japonicum and T. platycarpum had similar formulae described as 2n=16=12(M+m)+4mcs. In contrast, that of T. maruyamanum was 2n=16=14m+2mcs. The karyological data support the taxonomic study by Serizawa (1986, 1995), who treated the native lowland diploid Taraxacum in Japan as 2 species, T. platycarpum and T. maruyamanum.