Not out of the box: phylogeny of the broadly sampled Buxaceae

Abstract

The Buxaceae constitute a morphologically diverse phylogenetic lineage of six genera, which includes about 140 species. The most well-known genera are Buxus, Sarcococca, and Pachysandra. Few species of woody Styloceras grow on mid-elevations in the Andes mountains region. Didymeles, with three species endemic to Madagascar, and the monotypic Haptanthus from Honduras, are the most unusual members of the group. The infra-familial classification of Buxaceae is controversial, and molecular data about many species, especially Old World, is still lacking. We used broad taxonomic sampling and molecular data from four chloroplast markers, and the nuclear ribosomal ITS to estimate their phylogeny. These data provide phylogenetic placements of 50 species and enabled better estimates of boundaries in Buxaceae. We described two subfamilies, one monotypic genus, two Buxus subgenera, and one new species of Didymeles from Madagascar.

Differential Adaptation Has Resulted in Aggressiveness Variation of Calonectria pseudonaviculata on Hosts Buxus, Pachysandra, and Sarcococca

“…Sweet box is morphologically more like boxwood than is pachysandra; it is unclear whether this similarity in plant architecture or leaf physical characteristics might have some effect on the pace at which Cps isolates adapt to these host plants. Phylogenetically, pachysandra and sweet box are very close [ 40 ]. However, phenotypically, both boxwood and sweet box are woody, with smooth and shiny leaves arranged in a herringbone form, while pachysandra has larger, less-waxy leaves and an upright vining form [ 41 , 42 ].…”