(Floral biology of Vochysia cinnamomea Pohl (Vochysiaceae) in cerrados of the Triângulo Mineiro, MG). Vochysia cinnamomea is a small tree commom in the cerrado vegetation in southern areas of Central Brazil. The yellow zigomorphic flowers have a gamosepalous calix with a larger spurred lobe. The one-day flowers open during the morning and the only stamen is ejected during the anthesis leaving the pollen on the style, a kind of secondary pollen presentation. The most common visitors are Epicharis bees and other large Anthophoridae wich are the main pollinators, although hummingbirds and diurnal sphingids were also observed. The plant is partially self-compatible though mature selfed fruits were barely over a quarter of the crossed ones, and index of self-incompatibility (ISI) of 0.26. Self pollen tubes are arrested half way down the style in most of the observed pistils wich indicates a functional self-incompatibility mechanism similar to the observed in other species of Vochysia. Pollination and breeding systems features of V. cinnamomea are basically similar to the observed for other Vochysia species studied in Brazil, although most of them are more clearly self-incompatible. The partial self-compatibility found here may help to explain the occurrence of totally self-compatible species studied in Costa Rica.
Pollination; secondary pollen presentation; large bees; savanna; Vochysiaceae
