Aerangis kirkii (Rchb. f.) Schltr. - syn.Angraecum bilobum var. kirkii Rchb. f. - Orchidaceae
Rare endangered shade-loving epiphytic African orchid, native to the coastal forests of Kenya, Tanzania and Mozambique; flowers white, scentless during the day, pleasant white-floral scented in the twilight and night.
The „… pleasant white-floral flower scent is characterized by aspects reminescent of tuberose and gardenia. For the latter aspects, cis-4-methyldecano-5-lactone is responsible.“
The headspace contained 26.2% of (4S,5S)-4-methyldecano-5-lactone (named 'aerangis lactone', a 4-methyl dihydro jasmine lactone also present in Aerangis confusa flower scent), methyl (S)-3-methyloctanoate (1.9%) as olfactory important principles. Other (main) constituents were germacrene D (33.0%), benzyl acetate (17.3%), phenylethyl acetate (4.7%), and p-methylanisole (2.8%).
[Scent of a vanishing flora, Roman Kaiser, 2011, 253-255 and 304-305]
Aerangis biloba (Lindl.) Schltr. var. kirkii as Angraecum bilobum Lindl. var. kirkii
Warner, R., Williams, B.S., The orchid album, vol. 1885: t. 162 (1885) [J.N. Fitch]