Galanthus (convolute). He merged "Nivalis" and "Plicati" into series "Galanthus", and divided "Latifolii" into two subseries, "Glaucaefolii" and "Viridifolii" . Early molecular phylogenetic studies confirmed the genus was monophyletic and suggested four clades, which were labelled as series, and showed that Davis' subseries were not monophyletic. An expanded study in 2013 demonstrated seven major clades corresponding to biogeographical distribution. This study used nuclear encoded nrITS (Nuclear ribosomal internal transcribed spacer), and plastid encoded "matK" (Maturase K), "trnL-F", "ndhF", and "psbK–psbI", and examined all species recognised at the time, and also two naturally occurring putative hybrids. The morphological characteristic of vernation that
Galanthus nivalis (flowering stalk), which bears at the top a pair of bract-like spathe valves joined by a papery membrane. From between them emerges a solitary, pendulous, bell-shaped white flower, held on a slender pedicel. The flower consists of six tepals, also referred to as segments. The outer three are larger and more convex than the inner ones. The inner flower segments are usually marked on their outer surface with a green or greenish-yellow V- or U-shaped mark (sometimes described as "bridge-shaped") over the small sinus (notch) at the tip of each tepal. The inner surface has a faint green mark covering