New Chromosome Counts in Juncus (Juncaceae) Taxa from Korea

Juncus L. (Juncaceae) is a genus of annual and perennial herbs composed of approximately 310 species distributed worldwide, but more rarely found in the tropics. Despite an increasing number of karyologi-cal studies in Juncaceae, reports on chromosome numbers in Korean Juncus taxa have been scarce owing to the small chromosome size. Here, we present detailed information on chromosome numbers obtained from 36 indi-viduals of 10 Korean Juncus taxa. Chromosome numbers of eight taxa (J. diastrophanthus, J. prismatocarpus subsp. leschenaultii, J. krameri, J. papillosus, J. wallichianus, J. gracillimus, J. fauriei, and J. setchuensis) are reported for the first time. All studied taxa have different chromosome numbers and ploidy variations (2n= 30, 60, and 80) with small chromosomes. These ploidy level variations are of no systematic relevance in Korean Juncus taxa; however, this variation in chromosome number might provide additional evidence for the importance of morphological diversification via polyploidization including both auto-and allopolyploidization.

Automated summary

Juncus L. is a genus of herbs with approximately 310 species globally, but less commonly found in the tropics. This study presents detailed information on chromosome numbers from 36 individuals of 10 Korean Juncus taxa, revealing variations in chromosome numbers with no systematic relevance. The study suggests that this chromosome number variation could provide additional evidence for morphological diversification.