Morphological variability of the Caltha palustris L. complex (Ranunculaceae) in Poland

Abstract

The paper presents results of biosystematic analysis of the critical group of <em>Caltha palustris </em>L. based on 71 populations from Poland. After a preliminary statistical analysis, fourteen morphological characters (nine quantitative and five qualitative), describing size and shape of basal leaves and mature follicles as well as stem morphology, were selected for the clearest differentiation of the complex. Several groups of morphotypes were distinguished within the complex, based on the statistical analysis of this group of characters. Against this background the taxonomy of the complex is proposed. Two species - <em>Caltha laeta </em>Schott, Nyman and Kotschy and <em>Caltha palustris </em>L. - and three subspecies within <em>C. palustris </em>(<em>C. p. </em>subsp. <em>palustris</em>, <em>C. p. </em>subsp. <em>cornuta </em>(Schott, Nyman and Kotschy) Hegi and <em>C. p. </em>subsp. <em>radicans </em>(T.F. Forst.) Syme, were distinguished in Poland. The status of the taxa within the Polish flora is defined. The paper includes also a key for determination of the complex taxa, as well as their detailed descriptions.