Floral reversion and first record of pseudovivipary in some species of Poaceae

This contribution constitutes the first report of floral reversion and occurrence of pseudovivipary in Paspalum ceresia (Kuntze) Chase, P. stellatum Humb. & Bonpl. ex Flüggé and Thysanolaena latifolia (Roxb. ex Hornem.) Honda. Observations were made in material kept under cultivation in Buenos Aires (Argentina) since March 2001. Proliferating spikelets are described and illustrated, and some implications in the origin of spikelet organs are discussed. An up to date table including the genera of Poaceae where this phenomenon has been documented is also provided.