Is Lotus zhegulensis Klok. (Fabaceae) a separate species endemic of the Middle Volga Region or just a variety of a widespread L. corniculatus L.?

We have studied several samples from Lotus corniculatus s. l. and L. zhegulensis populations with the use of SSR sequenced nuclear (ITS) plastid (atpB-rbcL, ndhC-trnV, rpl32-trnL(UAG), trnH-psbA, trnL-trnF) markers. analysed 9 local Volga River valley ranging Ulyanovsk in north to Volgograd south, as well two Moscow Lipetsk Provinces. Analyses markers using STRUCRURE program divided sample into three genetic clusters. Populations Provinces, ‘locus classicus’ location Samara Province appeared be most genetically differentiated while all other were variously admixed. Low pairwise Fst values indicate low differentiation intraspecific nature revealed diversity. The DNA sequences analyzed yielded little information. Substitutions indels mostly autapomorphies characteristic separate specimens or small groups but not populations. Our study enables firmly conclude that right bank vicinity Zhiguli upland described are weakly and, hence, cannot regarded a species.