A numerical taxonomic analysis of the Medicago littoralis - M. truncatula complex.

An analysis of 152 populations of the Medicago littoralis Rhode – M. truncatula Gaertn. complex showed that the two putative species are separable, although all characters studied are overlapping. Some size differences previously used for discrimination did not appear under standard cultivation and are probably based on environmental modifications related to the different habitats of the species. Plants of M. littoralis of Israel, Greece, Italy, and Spain seemed to differ morphologically, the plants of each country being substantially discriminable from those of every other country. However, variation appeared continuous and overlapping and not conducive to formal infraspecific recognition. Plants of M. littoralis of the geographically closer combinations of these countries are more similar morphologically than are plants of the geographically more remote combinations.