Palynological studies of the argentinian species of Macroptiliurn (Fabaceae).

Abstract

The pollen morphology of nine species of Macroptiliurn (Benth.) Urb.: M. panduraturn (Benth.) Maréchal & Baudet, M. longepedunculatum (Benth.) Urb., M. lathyroides (L.) Urb., M. bracteatum (Benth.) Maréchal & Baudet, M. erythroloma (Benth.) Urb., M. fraternum (Piper) Juárez & Pérez, M. psammodes (Lindman) Drewes & Palacios, M. prostratum (Benth.) Urb. and M. arenarium (Bacigalupo) Drewes & Palacios were studied with the photonic and scanning electron microscope. It is possible to differenciate them in two groups: 1) an homogeneous one, section Macroptilium, with colporate, spherical and reticulate or microreticulate grains; 2) an heterogeneous one, section Microcochle (Benth.) Lackey, with porate or colporate, suboblate grains with different ornamentation. In the section Macroptiliurn the separation at species level is difficult due to the similarity of their grains, but in the section Microcochle they can be recognized by the type of ornamentation. The main purpose of this paper is to determine the pollen diagnostic characters that allow species identification.