Pollen morphology of the South American genus Lessingianthus (Vernonieae, Asteraceae) and its taxonomic implications.
ANGULO, M. B.; DEMATTEIS, M.
Taylor & Francis
Lugar: London; Año: 2010 vol. 49 p. 12 - 25
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 .