A new genus and species in Cupressaceae (Coniferales) from northern Vietnam, Xanthocyparis vietnamensis

Botanical explorations of heretofore poorly inventoried limestone formations in the northern Vietnamese border province of Ha Gang have yielded a new taxon of conifer that is to be classified in a cupressoid clade of Cupressaceae. It has foliage and ovuliferous cone characters that compare closely to Chamaecyparis nootkatensis (D. Don) Spach, as well as a feature peculiar to it and rare in conifers: the simultaneous occurrence of juvenile and mature leaves oil normal plagiotropic branching systems of mature trees. It is proposed in this paper to unite C. nootkatensis with the newly discovered species in a new genus Xanthocyparis; of this new genus and species a full description and illustrations are provided. Additional contributions to this paper include observations on its habitat, conservation status, and a taxonomic discussion.