Gagea trinervia and G. graeca, both diploid (2n = 24), share several features that appear unusual in the genus: white flowers, relatively late flowering, and red bulb tunics. They are genetically rather close, but can be distinguished with karyology and molecular markers (ITS-region). They indeed were thought to be conspecific by many authors. However, they exhibit huge ontogenetic, morphological and anatomical differences which point out a strongly divergent evolution: G. trinervia differs from G. graeca in having bulbils with stolon-like hypopodium, a regular sister bulbil at the immature stage, an unifacial, juvenile-like basal leaf to adult stage, few cauline leaves, few flowers and a low level of sexual reproduction. They form together Gagea sect. Anthericoides, the most early-branching clade of the genus, endemic to the Mediterranean. The closest species phylogenetically is the other diploid Gagea serotina, that we consider here included in the separate section Lloydia (Salisb.) Peruzzi & al. comb. & stat. nov.
On the phylogenetic position and taxonomic value of Gagea trinervia (Viv.) Greuter and G. sect. Anthericoides A. Terracc. (Liliaceae)
PERUZZI, LORENZO;
2008-01-01
Abstract
Gagea trinervia and G. graeca, both diploid (2n = 24), share several features that appear unusual in the genus: white flowers, relatively late flowering, and red bulb tunics. They are genetically rather close, but can be distinguished with karyology and molecular markers (ITS-region). They indeed were thought to be conspecific by many authors. However, they exhibit huge ontogenetic, morphological and anatomical differences which point out a strongly divergent evolution: G. trinervia differs from G. graeca in having bulbils with stolon-like hypopodium, a regular sister bulbil at the immature stage, an unifacial, juvenile-like basal leaf to adult stage, few cauline leaves, few flowers and a low level of sexual reproduction. They form together Gagea sect. Anthericoides, the most early-branching clade of the genus, endemic to the Mediterranean. The closest species phylogenetically is the other diploid Gagea serotina, that we consider here included in the separate section Lloydia (Salisb.) Peruzzi & al. comb. & stat. nov.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
