Abstract: The monotypic genus Lamiophlomis (including only L. rotata) and five species of Phlomis in the Lamiaceae were karyomorphologically studied. The interphase nuclei are all categorized to be round prochromosome type, and the mitotic-prophase chromosomes are all categorized to be interstitial type. The karyotype formulae are as follows: L. rotata, 2n=2x= 22=18m+4sm; P. umbrosa, 2n=2x=22=22m; P. ruptilis, 2n=2x=22=22m; P. betonicoides, 2n=2x=22=22m; P. melanantha, 2n=2x=22=22m(2sat); P. strigosa, 2n=6x=66= 60m+ 6sm. The basic chromosome number of Lamiophlomis is confirmed to be x=11, the same as that of Phlomis sect. Phlomoides, which shows that Lamiophlomis rotata should be better treated as a species of Phlomis.

Key words: Lamiophlomis rotata, Phlomis, chromosome number, karyotype