Preliminary analyses of the floral fragrances of species of Acineta, Houlettia, Luddemannia, Lycomormium, Paphinia, and Sievekingia (Orchidaceae)

We have previously reported on analyses of the floral fragrances of a number of species of orchids (Hills el al. 1968, 1972; Murrell et al. 1981; Williams et al. 1981). In this paper we report the results of our analyses of the floral fragrances of seven species in six genera of neotropical orchids. All of the species reported here are pollinated by male euglossine bees, or are confidently expected to be pollinated by male euglossine bees. There are several published observations of pollinators of several species in the genera we studied (see Williams 1982 for a list of euglossine-pollinated orchids and their pollinators, and Table 1 in this paper). The identifications of the floral fragrance components reported here are based on a comparison of relative retention times, co-injection of known with unknown compounds, and field bioassays. Additional techniques were previously described (Williams 1981). We have shown that this is a good method of verifying the identity of orchid floral fragrance compounds, especially of those orchids that are pollinated by male euglossine bees (Hills et al. 1972; Williams and Dodson 1972; Dodson et al. 1968; Dodson 1970, 1975). We hope to confirm these identifications by using combined capillary gas chromatography /mass spectrometry in the near future as these species come into flower in our greenhouse.