Pollen morphology of the South American genus Lessingianthus (Vernonieae, Asteraceae) and its taxonomic implications.

ANGULO, M.B.; DEMATTEIS, M.

GRANA

TAYLOR & FRANCIS AS

Año: 2010 vol. 49 p. 12 - 25

0017-3134

AbstractThe pollen grains of 111 species of Lessingianthus H. Rob. were analysed. Almost all  the species belong to the type “B”pollen, characteristic of the genus. These grains are oblate-spheroidal, spheroidal to prolate-spheroidal (P/E 0.93–1.04),echinolophate, 3-colporate, with lacunae  in a regular pattern, without polar lacunae. However, some species show varia-tions of this basic type. The types “B-1”, “B-2” and “B-3” grains are respectively 3-porate lacking equatorial lacunae, 3-porate with equatorial lacunae and 3-colporate, psilolophate. Also, one species showed type “D” pollen, a palynomorphpresent in other genera of the tribe but not reported until now for Lessingianthus. The analysis confirms that the species ofthe genus constitute well-defined groups based on the pollen characteristics. The results ascertain that the pollen morphol-ogy is a significant feature in the identification and delimitation of species and genera of Vernonieae.