Morphological variability of rosette leaves within Sempervivum ciliosum and S. ruthenicum complexes (Crassulaceae): The geometric morphometrics approach

The yellow-flowered Sempervivum species from the Balkan Peninsula, tentatively divided into Sempervivum ciliosum (S. ciliosum, S. galicicum, S. jakucsii, S. klepa, S. octopodes) and S. ruthenicum complexes (S. kindingeri, S. leucanthum, S. ruthenicum, S. zeleborii), are well known for their pronounced phenotypic plasticity, especially in the vegetative parts, resulting in exceedingly complicate infrageneric taxonomy. Extensive studies dealing with the variability of qualitative and quantitative traits, such as the shape and size of the rosette leaves, were not conducted in the past. This study aimed to analyse the extent of morphological variability of the rosette leaves regarding their shape and size and evaluate their potential to resolve taxonomic doubts. For this purpose, geometric morphometrics, as a tool for analysing minute shape variability, was used to discriminate mentioned species. The variability of the rosette leaves was statistically analysed within 15 populations using univariate (ANOVA) and multivariate statistical analysis (MANOVA, PCA, DA). Obtained results indicated highly statistically significant differences in rosette leaf shape and size between analysed complexes and species.