The Buxaceae are a small

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

of six genera and about 123 known species of

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...

s. They are shrubs and small

tree In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are ...

s, with a cosmopolitan distribution. A seventh genus, sometimes accepted in the past (''Notobuxus''), has been shown by genetic studies to be included within ''

Buxus ''Buxus'' is a genus of about seventy species in the family Buxaceae. Common names include box or boxwood. The boxes are native to western and southern Europe, southwest, southern and eastern Asia, Africa, Madagascar, northernmost South ...

'' (Balthazar ''et al.'', 2000). The family is recognised by most taxonomists, and it is commonly known as the box family. However, its placement and circumscription has varied; some taxonomists treated '' Styloceras'' in its own family Stylocerataceae, '' Didymeles'' in its own family Didymelaceae, '' Haptanthus'' in Haptanthaceae (now all included in Buxaceae)), and formerly '' Simmondsia'' was included, which is not related and now usually placed in its own family Simmondsiaceae. The

APG II system The APG II system (Angiosperm Phylogeny Group II system) of plant classification is the second, now obsolete, version of a modern, mostly molecular-based, system of plant taxonomy that was published in April 2003 by the Angiosperm Phylogeny Gr ...

of 2003 recognises the family, but in a new circumscription in that it includes the genus '' Didymeles'' (two species of evergreen trees from Madagascar). However, APG II does allow the option of segregating this genus as family Didymelaceae, as an optional segregate. This represents a slight change from the

APG system The APG system (Angiosperm Phylogeny Group system) of plant classification is the first version of a modern, mostly molecular-based, system of plant taxonomy. Published in 1998 by the Angiosperm Phylogeny Group, it was replaced by the improved A ...

of 1998, which firmly recognised both families as separate. In both APG and APG II, the family Buxaceae is unplaced as to order and left among the basal lineages of the

eudicots The eudicots, Eudicotidae, or eudicotyledons are a clade of flowering plants mainly characterized by having two seed leaves upon germination. The term derives from Dicotyledons. Traditionally they were called tricolpates or non-magnoliid dicots ...

. Th
AP website
suggests instating the order

Buxales The Buxales are a small order of eudicot flowering plants, recognized by the APG IV system of 2016. The order includes the family Buxaceae; the families Didymelaceae and Haptanthaceae may also be recognized or may be included in the Buxaceae. ...

for this family and the family Didymelaceae. In the

APG IV system The APG IV system of flowering plant classification is the fourth version of a modern, mostly molecular-based, system of plant taxonomy for flowering plants (angiosperms) being developed by the Angiosperm Phylogeny Group (APG). It was published ...

of 2016, ''Haptanthus'' and ''Didymeles'' are included in Buxaceae, which is the only family in Buxales.

References

*Balthazar, M. von, Peter K. Endress, P. K., and Qiu, Y.-L. 2000. Phylogenetic relationships in Buxaceae based on nuclear internal transcribed spacers and plastid ''ndhF'' sequences. ''Int. J. Plant Sci''. 161(5): 785–792 (availabl
online
.

in L. Watson and M.J. Dallwitz (1992 onwards)
''The families of flowering plants''
Eudicot families {{eudicot-stub