Variation of seed morphology of Trollius europaeus L. and Trollius altissimus Crantz (Ranunculaceae)

Abstract

The aim of this study was to investigate seed morphology and intra- and inter-population variation of seeds of <em>Trollius europaeus</em> L. and <em>Trollius altissimus</em> Crantz., two controversial species regarding their taxonomical position. We analyzed seed-coat microsculpture and some biometrical traits (length and width, width/length ratio, volume and projected perimeter). Seed sculpture did not differ between species, but seeds of <em>T. altissimus</em> were usually larger than seeds of <em>T. europaeus</em>. Although species differed significantly in seed morphology, it was possible to show the populations of both species that were similar regarding the analyzed seed traits. We noted a significant inter-population differentiation of seeds in both species with respect to seed-coat microornamentation and biometrical traits. We conclude that <em>T. europaeus</em> and <em>T. altissimus</em> are probably not two distinct species, but <em>T. europaeus</em> should be divided into two lower taxa in the rank of variety or subspecies.