Several phylogenetic studies of the Amaryllidaceaes.s. (Amaryllidaceae subf. Amaryllidoideae sensu APG III (Chase et al., 2009)) using plastid and nuclear DNA sequences have been undertaken (trnL-F and rbcL (Meerow et al. 1999); matK (Ito et al. 1999); matK and ITS (Lledó et al., 2004); ndhF and ITS (Meerow et al. 2006); ITS, matK and trnL-F (Larsen et al. 2010). In all of these phylogenetic studies Galanthus and Sternbergia were resolved in a clade (Eurasian clade of Meerow et al. 1999, 2006 and Lledó et al. 2004, or Mediterranean clade of Ito et al. 1999) also containing Leucojum L. (including Acis Salisb.), Narcissus L., Lapiedra Lag. and Pancratium Dill. ex L. (and sometimes Hannonia Braun-Blanq. & Maire, Lycoris Herb., Ungernia Bunge and Vagaria Herb.). Intergeneric relationships were generally inconsistent; however, a well supported relationship between Leucojum and Galanthus was consistently observed across the studies. A sister-group relationship of Sternbergia to Narcissus was confirmed in Ito et al. (1999), Graham & Barrett (2004), Meerow et al. (2006) and Gage et al. (2011).
The phylogenetic study of Lledó et al. (2004) focusedon the relationship between the genera Leucojum and Galanthus, using plastid (matK) and nuclear ribosomal DNA (ITS) and comparing them to a matrix of morphological characters. The analysis included all Leucojum species and most Galanthus species or at least representatives of all of the series and subseries of the genus sensu Davis (1999, 2001), together withclosely related genera Lapiedra, Narcissus, Pancratium, Sternbergia and Vagaria. A strongly supported cladecorresponding to tribe Galantheae sensu stricto including only Galanthus, Leucojum and Acis emerged. Leucojum was revealed as paraphyletic and the genus Acis was resurrected to accommodate all Leucojum species except Leucojum vernum L. and Leucojum aestivum L. Galanthus, although nestled in Leucojum/Acis, is monophyletic. Several morphological synapomorphies support this conclusion: usually only two leaves per bulb; perianth whorls differ in size, outer whorl being roughly twice the size as the inner; inner perianth segments consistently have green marks, more or less V- or U-shaped; outline shape of the anthers is more or less sagittate and their apices are furnished with a long point (apex point short in G. platyphyllus Traub & Moldenke); and a base chromosome number of 12. In this study Galanthus was shown to be divided into four well supported clades. The one containing G. nivalis L., G. reginae-olgae Orph. and G. plicatus M.Bieb. is monophyletic and corresponds to series Galanthus (sensu Davis 1999, 2001). The remaining three clades are formed by species in series Latifolii (sensu Davis 1999, 2001), which is paraphyletic because series Galanthus is nestled within it. The relationship between G. krasnovii Khokhr. and G. platyphyllus was well supported and concurs with morphological synapomorphies suggested in Davis (1999) such as more or less club-shaped bulbs, broad green leaves and marginate inner perianth segments. The pairing of morphologically distinct G. alpinus Sosn. and G. transcaucasicus Fomin was well supported and it was tentatively explained by introgression in Davis (1994).
A phylogenetic study of Eurasian Amaryllidaceae (Meerowet al. 2006), showed discrepancy between the ndhF and the ITS analyses. NdhF results placed Hannonia, Lapiedra and Vagaria (tribe Pancratieae Salisb.) within the Galantheae clade in most trees, while Galantheae s.s. is weakly supported by the ITS results. Infrageneric relationships were largely unresolved, showed discrepancies between analyses and only included a limited taxa sampling.
A further study by Larsen et al. 2010 aimed at providing a phylogenetic framework for selection of candidate plants for lead discovery in relation to Alzheimer's disease. Phylogenetic analyses using ITS, matK and trnL-F regions supported strongly a monophyletic tribe Galantheae in the narrow sense, including only Acis, Galanthus and Leucojum. Infrageneric relationships of Galanthus only partly supported previous classifications. Davis (1999, 2001) divided Galanthus into two series: series Galanthus included only G. nivalis, G. reginae-olgae and G. plicatus and corresponded to well-supported clade B in this study; series Latifolii included the remainder of the genus except Galanthus trojanus A.P.Davis & Özhatay (Davis and Özhatay, 2001), which is of uncertain affinity (Davis, 2001) and was not included in this study. In the classification by Davis (1999,2001), series Latifolii is divided into two subseries (Glaucaefolii and Viridifolii); however these were notmonophyletic in this study, corresponding with the results of Lledó et al.(2004). The pairing of G. koenenianus Lobin and G. alpinus was well supported and agrees with morphological synapomorphies suggested in Davis (1999, 2001) such as glaucous leaves, supervolute vernation and a single markin the apex of each inner perianth segment. In Lledó et al. (2004), G. alpinus is sister to the morphological distinct G. transcaucasicus, a little known species of uncertain affinity (Davis, 1999, 2001). An Armenian sample of G. artjuschenkoae Gabrieljan (published as a new species in Gabrieljan, 1999) was also included in the analysis and it showed little sequence divergence from G. lagodechianus Kem.-Nath. (also in Armenia and Azerbaijan). Davis (2001) considered G. artjuschenkoae asynonym of G. transcaucasicus and this study suggests conspecificity with G. lagodechianus seems likely. Also in the same clade as G. lagodechianus are G.rizehensis Stern. and G. woronowii Losinsk.;the former two are morphologically similar and they all have a sympatric distribution (Davis, 1999, 2001). In Lledó et al. (2004), G. lagodechianus was sister to G. gracilis Celak.; this was not supported in any of the analyses in Larsen et al. 2010 or by morphology or distribution (Davis, 1999, 2001).
Meerow et al. (2006) explored intergenericrelationships in Eurasian Amaryllidaceae and showed that tribe Narcissae (Narcissus and Sternbergia) was supported and together with Pancratium they form a clade. However, these results were not completely supported in the ITS analysis. This study only included four Sternbergia taxa (S. colchiciflora Waldst. & Kit., S. greuteriana Kamari & R.Artelari, S. lutea (L.) Ker Gawl. ex Spreng., and S. sicula Tineo ex Guss.), which were placed in a consistently well-supported clade. The results showed little divergence between these taxa and this is not surprising since it has been shown that three of them (S. greuteriana, S. lutea, and S. sicula) may be conspecific (Gage & Wilkin, 2008). A much higher level of sequence divergence was observed between S.colchiciflora and the remaining taxa.
The only phylogenetic study focusing on infrageneric relationships in Sternbergia was published by Gage et al. (2011). Both plastid (ndhF and matK) and nuclear (ITS) DNA genes were used and all Sternbergia taxa were represented by at least one accession, except S. minoica Ravenna and S. schubertii Schenk. The monophyly of Sternbergia was supported and the genus is composed of two main subclades: a) S. colchiciflora sister to S. vernalis (Mill.) Gorer & J.H.Harvey, S. candida B.Mathew & T.Baytop and S. clusiana (Ker Gawl.) Ker Gawl. ex Spreng., with this clade in turn sister to b) S. lutea and its allies. Lack of resolution in the S. lutea complex offers further support to the suggestion of conspecificity of S. greuteriana, S. lutea, and S. sicula suggested in Gage & Wilkin (2008). The relationship between the two vernal species (S. vernalis and S. candida) is strongly supported in all of the analyses, suggesting a single origin of vernal flowering in Sternbergia.