Pollen morphology of six species belonging to genera Ellisiophyllum and Sibthorpia (Plantaginaceae tribe Sibthorpieae) was studied using light and scanning electron microscopy. The data were analyzed in the light of the first phylogenetic analysis including all but one species of the tribe using DNA sequence data from nuclear ribosomal (ITS) and plastid trnL-F region. Pollen grains in representatives of this tribe are 3-colpate, occasionally 3-porate, suboblate to prolate; mainly medium-sized, rarely small. One major pollen type (3-colpate) is recognized in the tribe. Within this pollen type, six subtypes are distinguished based on their exine sculpture, pollen grain size, length of the apertures, and exine thickness. The obtained results confirm that pollen characters are useful for species identification. Palynomorphological data are consistent with the results of the molecular phylogenetic analyses. All studies support a sister relationship of the widespread European Sibthorpia europaea with the widespread South American Sibthorpia repens and a sister relationship of two insular species, the Balearic Sibthorpia africana and the Madeiran Sibthorpia peregrina. Pollen grains in the tribe Sibthorpieae have both reticulate exine sculpture characteristic for representatives of the Russelieae–Cheloneae–Antirrhineae clades of Plantaginaceae, and also nanoechinate sculpture, which is typical for the Veroniceae and Plantagineae clades of that family. Also, in Sibthorpia repens, we observe a possible transition from the colpate type to the porate type typical for taxa of Plantago and Littorella.

Mosyakin S. L. & Tsymbalyuk Z. M.: Pollen morphology of tribes Aptosimeae and Myoporeae supports the phylogenetic pattern in early-branching Scrophulariaceae revealed by molecular studies. — Willdenowia 45: 209–222. 2015. — Version of record first published online on 15 July 2015 ahead of inclusion in August 2015 issue; ISSN 1868-6397; © 2015 BGBM Berlin. DOI: http://dx.doi.org/10.3372/wi.45.45207 Pollen morphology of six species representing three genera of tribe Aptosimeae and six species representing two genera of tribe Myoporeae (Scrophulariaceae) is described and illustrated using light microscopy (LM) and scanning electron microscopy (SEM). Pollen grains in Aptosimeae are 3-syncolporate, prolate, sometimes oblate-spheroidal in shape; mainly medium-sized, occasionally in some taxa small; exine sculpture striate, rarely with microperforations and small granules. Pollen grains in Myoporeae are 3-colpate-diorate, spheroidal, rarely oblate-spheroidal or prolate in shape; mainly medium-sized, occ...

Recent molecular phylogenetic studies of Dipsacales place Symphoricarpos in a clade containing Leycesteria, Triosteum, and Lonicera. The aim of this research was to analyze the palynomorphological features of taxa of Symphoricarpos, and to compare the results with the taxonomic classification scheme and molecular phylogenetic data. Pollen morphology of 20 herbarium specimens belonging to 12 taxa of Symphoricarpos was studied using both light microscopy and scanning electron microscopy. Pollen grains are 3(4)-colporate, obtate to subprolate (P/E = 0.73–1.21) in shape; medium- and large-sized (P = 27.93–62.51 μm, E = 25.27–69.16 μm). Three pollen types of exine sculpture are recognized in the genus: type I – psilate-perforate, type II – microechinate-nanoechinate, and type III – echinate-microechinate-nanoechinate. Within these pollen types, seven subtypes are distinguished based on details of the exine sculpture, pollen size, details of colpi, and presence/absence and width of annuli. It has been established that the important diagnostic features of the species level for the purposes of taxonomy of Symphoricarpos are the size of pollen grains, details of the colpi and ores, presence/absence and width of the annuli, and exine sculpture. The pollen morphology of Symphoricarpos taxa allows the establishment of hypotheses regarding the evolution of exine sculpture. In particular, we assume that there is an evolutionary trend towards a decrease in the size and number of echini and microechini. Pollen grains with an echinate-microechinate-nanoechinate exine sculpture are hypothesized to be a plesiomorphic condition within the genus Symphoricarpos.

Pollen morphology of 34 herbarium specimens belonging to 17 taxa of the genus Valeriana was studied using light and scanning electron microscopy. The aim of this research was to evaluate the taxonomical value of palynomorphological data for species-specific identification. Pollen grains are monads, radially symmetrical, isopolar, tricolpate, oblate to prolate (P/E = 0.69–1.59); medium- or large-sized (P = 26.60–66.50 µm; E = 23.94–57.19 µm). Colpi are long, medium-length or short, with acute, obtuse or rounded ends. Four types and eight subtypes of exine sculpture were recognised: type I—echinate-verrucate (5 spp.), type II—echinate-nanoechinate-verrucate (10), type III—echinate-microechinate-nanoechinate-verrucate (1), type IV—echinate-microechinate-nanoechinate (1). Additional characters of taxa of Valeriana diagnostic at species level for the purposes of taxonomy are: size of pollen and colpi, exine sculpture: presence/absence of verrucae, their form, size and form of echini/microechini/nanoechini, their number, pattern of tectum in areas between echini, exine thickness in mesocolpia and apocolpia. Our palynomorphological data support the results of molecular phylogenetic studies. The close phylogenetic relationships of the species V. montana, V. tripteris, V. supina and V. pyrenaica are also supported by their palynomorphological characters, such as exine sculpture (type I). Cluster analysis mainly supports the definition of pollen types and subtypes (based on qualitative data), since species are grouped as five separate branches. The pollen grains of five taxa were analysed for the first time in the current study.