The chromosome numbers and karyotypes of five species of the genus Leontopodium (Asteraceae) from Southeastern QinghaiTibet Plateau, Southwest China were investigated. Three species were studied karyomorphologically and reported for the first time: L.franchetii 2n=2x=26=6M+18m+2sm, 2A; L.calocephalum 2n=4x=48=3M+43m+2sm, 1B; L.stracheyi 2n=4x=48=13M+35m, 1A. Two species L.souliei and L.sinense presented different chromosome numbers and karyotypes from the previous reports, that is, L.souliei 2n=2x=24=13M+8m+3sm, 1B; L.sinense, the population collected at altitude 2406m a.s.l. Muli County, Sichuan Province: 2n=2x=26=4M+22m, 1B, the population collected at altitude 3074m a.s.l. Muli County, Sichuan Province: 2n=4x=52=16M+36m, 1B. The comparison of existent chromosomal data indicates that Leontopodium is a genus with symmetry karyotype, but diversified obviously among different species. Polyploidization might have played an important role in the speciation and evolution of Leontopodium on the QinghaiTibet Plateau and its southeastern peripheral regions.

The leaf epidermis of 19 species representing all four subseries of Cyrtomium， and 15 allied groups was investigated under light microscopy, of which twelve species including types of three subseries of Cyrtomium were observed under scanning electron microscopy. The form of epidermal cells of the Cyrtomium was usually polygonal or irregular, with the anticlinal walls nearly straight, arched, sinuolate, sinuous to sinuate. The stomatal apparatus in all species only existed on the abaxial epidermis. The major stomatal apparatus was anomocytic, while diacytic and polocytic types also occurred in Cyrtomium. The stomata on a single leaf belonged to two or more types in most species. Under SEM, the inner margin of the outer stomatal rim ranged from nearlysmooth to sinuolate or erose, and the cuticular membrane of the leaf epidermis was striated, but sometimes with granula. The present study implied that there are no distinct characters of the leaf epidermis to distinguish and diagnose two series and four subseries of Cyrtomium in Shing′s classification.

Leaf epidermis of 16 species from Chelonopsis and its related taxa, Bostrychanthera deflexa, were examined under both light microscope and scanning electronic microscope. As a result, all species are characterized with irregular leaf epidermis cells, except those of sect. Aequidens (C.souliei, C.forrestii and C.albiflora), which are nearly rectangular. Two kinds of anticlinal walls of adaxial epidermis cells can be distinguished: sinuous and straightarched. Stomatal apparatuses, whose density varies in different species, can only be found in abaxial epidermis. Highly consistent in all examined species are the type of guard cells and the smooth inner margin of outer stomatal rim. What’s more, three cuticular patterns are recognized: ridged, long striped, and with snow flaked or granulate appendages. Consequently, Characters of leaf epidermis in Chelonopsis, such as pattern of epidermal cell and cuticular ornamentation, are of great significance in understanding the relationships at both infrageneric and interspecific levels. In addition, density of stomatal apparatuses may be correlated with the habitat of some species in Chelonopsis.