Taxonomic Significance of Carotenoids

GOODWIN 1 , reviewing the distribution of carotenoids in non-photosynthetic tissue, came to the conclusion that it was very difficult to see their taxonomic significance. Rubixanthin seemed to be restricted to Rosa spp. 2 and it was suggested that, if a carotenoid mixture contained significant amounts of rubixanthin, then one could say with some confidence that the source of rubixanthin was the hips of a species of Rosa 1 . Rubixanthin, however, has been identified in several other plants, namely, Cuscuta salina , C. subinclusa 3 and Gazania rigens 4 . Valadon 5 has also identified this pigment in the orange peel fungus, Peziza (Aleuria) aurantia , but Jensen 6 failed to confirm this result and had found a new pigment. With a view to finding whether rubixanthin was restricted to some members of the higher plants, we have reinvestigated the carotenoid composition of the orange peel fungus.