Pollen morphology of some species of the genus Cephalaria Schrad. (Caprifoliaceae) and its significance for taxonomy

Abstract

Palynology gives the evidence for identification and elimination of taxonomically complex genera. Pollen morphology of nine species (three subg., three sect.) of the genus Cephalaria Schrad. was studied using light microscopy and scanning electron microscopy. Pollen grains of all investigated species are triporate, suboblate to subprolate (P/E = 0.75-1.28), and large-sized (P = 58.52 μm-114.38, E = 63.84-119.70 μm). The outline of pollen grains in equatorial view is circular or elliptic, in polar view circular, circular-triangular, or triangular. Pores are distinct, lolongate, elliptic, or circular, with an annulus, operculum, and distinct or indistinct, wide halo surrounding the aperture. Exine sculpture is echinate-microechinate or echinate-microechinatenanoechinate. Additional diagnostic characters at the species level in Cephalaria Schrad. that can be used for the purposes of taxonomy are size of pollen grains and pores, the shape of pores, the width of the annulus, structure of the exine, dimension of echini and microechini, location of microechini, and presence/absence of nanoechini. Palynomorphological data are compared with the taxonomical classification system of investigated taxa. It is shown that pollen grains morphology of the genus Cephalaria Schrad. is similar to the pollen morphology of the genus Dipsacus L., which confirms their inclusion in the Dipsaceae tribe.

Phenolic Composition and Antioxidant Activity of Plants Belonging to the Cephalaria (Caprifoliaceae) Genus

“…The genus Cephalaria was previously placed in the Dipsacaceae Juss. family [ 11 , 12 , 13 ]. However, according to two latest versions of the system of the Angiosperm Phylogeny Group [ 14 , 15 ], the Dipsacaceae family belongs to the Caprifoliaceae Juss.…”

“…of subfam. Dipsacoideae A. Eaton [ 13 ]. The genus encompasses approximately 95 species [ 16 , 17 , 18 ] that have been identified especially in the Mediterranean Basin and adjacent western Eurasia which are the major centers of biodiversity at a global level [ 19 , 20 , 21 , 22 ].…”

“…The genus encompasses approximately 95 species [ 16 , 17 , 18 ] that have been identified especially in the Mediterranean Basin and adjacent western Eurasia which are the major centers of biodiversity at a global level [ 19 , 20 , 21 , 22 ]. Several species occur also in Asia and eastern and southern Africa [ 13 , 23 , 24 , 25 ]. Plants belonging to the Cephalaria are annual, biennial or perennial herbs with glabrous or hairy stems and very variable leaves (most heterophyllous).…”

Taxonomic significance of pollen morphology of Pterocephalus plumosus (Caprifoliaceae)

“…It is well known that the morphological characteristics of pollen grains as additional diagnostic features are often used in the taxonomy (e.g., Mosyakin & Tsymbalyuk 2015Bellonzi et al 2020;Albach et al 2021;Gasparino et al 2021;Tsymbalyuk et al 2021aTsymbalyuk et al , b, 2022etc.). Comparative palynomorphological studies of Dipsacaceae s.str.…”

Morphology of pollen grains of Weigela floribunda (Caprifoliaceae): application in taxonomy

“…In general, the methods used in the present study were the same as those we used earlier (Tsymbalyuk et al, 2020(Tsymbalyuk et al, , 2021. Pollen grains were studied using both light microscopy (LM) and scanning electron microscopy (SEM).…”