Crocus forms a monophyletic clade, with a basal polytomy of four subclades. The first clade (A) corresponding to section Crocus, but including C. sieberi and several closely related species (originally included in section Nudiscapus series Reticulati). The remaining three clades (B-D) include all the remaining species of section Nudiscapus. Of these, B and C are small, corresponding to series Orientales and Carpetani respectively, with all remaining series in the large D clade. The exception is C. caspius, originally in series Biflori, which segregates in clade B. Thus, although division of the genus into two sections is well supported, no single morphological character defines these two groups. The C. sieberi group are assumed to have lost their prophyll secondarily. Of the series, eight could be shown to be monophyletic; Crocus, Kotschyani and Scardici (section Crocus) and Aleppici, Carpetani, Laevigati, Orientalis and Speciosi (section Nudiscapus). Flowering season did not correspond to molecular groupings and nor did any of the previously used morphological characteristics, indicating a high degree of homoplasy, in which traits are gained or lost independently in different lineages. The remainder of the series could not be supported as natural groupings. Mathew's concept of subspecies status within C. biflorus could not be supported, each being considered a separate species, resulting in the genus having at least 150 species.
Crocus forms a monophyletic clade, with a basal polytomy of four subclades. The first clade (A) corresponding to section Crocus, but including C. sieberi and several closely related species (originally included in section Nudiscapus series Reticulati). The remaining three clades (B-D) include all the remaining species of section Nudiscapus. Of these, B and C are small, corresponding to series Orientales and Carpetani respectively, with all remaining series in the large D clade. The exception is C. caspius, originally in series Biflori, which segregates in clade B. Thus, although division of the genus into two sections is well supported, no single morphological character defines these two groups. The C. sieberi group are assumed to have lost their prophyll secondarily. Of the series, eight could be shown to be monophyletic; Crocus, Kotschyani and Scardici (section Crocus) and Aleppici, Carpetani, Laevigati, Orientalis and Speciosi (section Nudiscapus). Flowering season did not correspond to molecular groupings and nor did any of the previously used morphological characteristics, indicating a high degree of homoplasy, in which traits are gained or lost independently in different lineages. The remainder of the series could not be supported as natural groupings. Mathew's concept of subspecies status within C. biflorus could not be supported, each being considered a separate species, resulting in the genus having at least 150 species.