Petasites albus (L.) Gaertner as a new record is reported for the first time from Hyrcanian forest zone in north of Iran. The species is different from previously known species (Petasites hybridus (L.) P. Gaertner) due to having permanent and white-arachnoid indumentum on below the surface of leaves, longer inflorescence and white flowers with glandular hairs on the phyllaries.

During our research on the genus Jurinea (Asteraceae) in Chaharmahal and Bakhtiari Province, specimens collected from the northwest and west of the province were compared with the related type specimens and the original protologues. This analysis revealed that the type specimen of J. viciosoi lacks capitula and, therefore, requires epitypification. Accordingly, an epitype is designated here, selected from our recent collections at the type locality. Jurinea viciosoi has been traditionally distinguished from J. meda primarily based on decurrent leaves and some minor morphological characters. However, extensive field observations and herbarium studies demonstrated that these characteristics are highly variable and frequently occur within populations of J. meda. As a result, we confirm that J. viciosoi should be treated as a synonym of J. meda. Additionally, based on the examination of numerous flowering and fruiting specimens, a comprehensive and updated description of J. meda is provided here.

Carduus L. (Asteraceae) comprised about 90 species of which 8 of them are distributed in Iran. From these only one species is endemic. The pollen morphology of eight species of Carduus was investigated using light and scanning electron microscope (SEM). The pollen type was sub-oblate to oblate-spheroidal, with echinate sculpturing. The grains sizes varies from 35.76-50.46 µm in polar view and from 37.38-59.63 µm in equatorial view. Palynological data are useful characters to separate studied species. The out-group species belong to the genus Cirsium Mill. and are located in a distinct cluster. The obtained species relationships are in agreement with the morphological results and previous taxonomic treatment of the genus.

Four new species of the genus Cousinia are described from Iran. C. barezica is based on a specimen collected from Barez mountain chains. The species belongs to the section Spinuliferae and related to C. longifolia and C. sicigera. It however, differs from both by having discolored leaves. C. isfahanica another new species from the section Rigidissimae is related C. rigidissima and C. auranti both from Afghanistan. This species has been based on a specimen collected from Isfahan, Semirom. C. maassoumii is described from adjacent localities of Delijan and Arak cities. It is from the section Pugioniferae and most closely related to C. macroptera but having different leaf and indumentum characters. C. pseudocandolleana is described based on specimen from Khorasan province. It is closely related to C. candolleana an endemic of Hamadan province, but differs from it by having stem and stem leaf characters.

The pollen grains of 32 populations from 13 genera belonging to the tribe Anthemideae - Asteraceae (one to three populations of each species) from Iran were studied by light and scanning electron microscopes. Pollen grains of all the studied samples were tricolporate. Based on pollen shape, 55, 22, 15 and 8 % were oblate- sp heroidal, suboblate, spheroidal and prolate - spheroidal, respectively. The pollen grains with oblate- spheroidal and spheroidal shapes were common among the genera studied.The pollen grains of all taxa were operculate and tricolporate. The pollen ornamentat ions were echinate perforate except Artemisia that was spinulose non- perforate in SEM.The dendrogram obtained from UPGMA method based on four quantitative and qualitative characters was classified into two main clusters. The first cluster (A) includes pop ulations of Artemisia which show "Artemisia - type" pollen, while the second cluster (B) comprises of the rest of the taxa which have pollen grains of "Anthemis - type". The subcluster B-1 possesses samples with bigger (polar axis 28.64- 32.5 mm and equatorial axis 30.65- 33.2 mm ) pollen grains and subcluster B - 2 comprised of populations with smaller (polar axis 21.69 - 30.38 mm and equatorial axis 23.29-32.4 mm ) pollen grains. The results showed that pollen micromorphological characters could be utilized in inter pretation of intergeneric relationship of tribe Anthemideae. Moreover, pollen size and shape were determined as taxonomic diagnostic characteristics.

Artemisia L. is the largest genus of the Anthemideae tribe and one of the largest genera in the family Asteraceae. Globally, the number of species of this genus has been more than 500 species. A number of 34 of these species have been reported in Iran, with 8 species in Isfahan province. The wide distribution of Artemisia species in Iran makes this genus one of the main elements of the Irano-Turanian region. In order to morphologically investigate the genus Artemisia, the quantitative and qualitative characters related to reproductive and vegetative structures of this plant were collected in 64 samples. The researchers obtained the cluster diagrams and principal component analysis (PCoA) for the morphological characters of the specimens by using GenAlEx 6. 5 and NTsys 2. 02 software. In the cluster diagram, the Seriphidium Besser ex Less. Dracunculus Besser Rydb. and Artemisia subgenera were placed in separate clusters and next to each other. The results of the present study showed that some traits such as gender and situation of flowers in the capitulum, indumentum of the stem and receptacle, the situation of petiole at the basal and middle leaves, trichrome on both sides of the leaf surface, and the shape of outer phyllaries and their indumentum had more taxonomic value. Finally, the paper presents an identification key for the Artemisia species in Isfahan province, Iran.