The distribution of the xanthophyll loroxanthin and its systematic significance in the colonial Volvocales (Chlorophyta)

Abstract

The distribution of the xanthophyll loroxanthin [(3R,3′R,6′R)-β,ε-carotene-3,19,3′-triol] within colonial volvocalean families was analyzed by reversed-phase high pressure liquid chromatography (rP-HPLC). The results demonstrate that loroxanthin is a physiological marker delineating the families Tetrabaenaceae Nozaki et Itoh and Goniaceae (Pascher) Pascher. Thus loroxanthin may be considered to be of systematic significance within the Volvocales, and its use as a marker supports recent ideas on phylogenetic relationships. Within the Volvocaceae Ehrenberg, its infraspecific disjunct distribution indicates that it is not useful systematically in this family and that it varies even within a morphologically defined species. The pattern of loroxanthin distribution was compared with molecular data and traditional characters.