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

ANGULO, M. B.; DEMATTEIS, M.

GRANA

Taylor & Francis

Lugar: London; Año: 2010 vol. 49 p. 12 - 25

0017-3134

The pollen grains of 111 species of Lessingianthus H. Rob. have been analyzed. Almost all the species presented 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 showed variations of this basic type. The types “B-1”, “B-2” and “B-3” were respectively 3-porate lacking equatorial lacunae, 3-porate with equatorial lacunae and 3-colporate, psilolophate. Also, one species showed type “D” pollen, a palynomorph present in other genera of the tribe but not reported until now for Lessingianthus. The analysis confirms that the species of the genus constitute well-defined groups based on the pollen characteristics. The results ascertain that the pollen morphology is a significant feature in the identification and delimitation of species and genera of Vernonieae .