 Increased surface area and irregularity of the pollen receptacle, caused by swellings, hairs, grooves or ridges often ensure a more efficient pollen deposition.After elongation of the style, animals transport the pollen to flowers in the female or receptive stage with exposed stigmatic surfaces.A pollen catapult mechanism is present in the genera "Molopanthera" and "Posoqueria" (tribe Posoquerieae) that projects a spherical pollen mass onto visiting sphingidae.