 Species of the genus "Cypripedium" (lady slippers) of orchids trap insects temporarily to ensure pollination.Plants in the genus "Ceropegia" attract pollinating small flies (usually female) in a wide range of families, including Milichiidae, Chloropidae, Drosophilidae, Calliphoridae, Ephydridae, Sciaridae, Tachinidae, Scatopsidae, Phoridae, and Ceratopogonidae, and the pollinaria always attach to their probosces.An analysis of the scents emitted by "Ceropegia dolichophylla" showed the presence of spiroacetals which are rare in plants and common among insects.