flowering
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). The biological function of a flower is to facilitate reproduction, usually by providing a mechanism ...
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 placed in the family
Cornaceae
The Cornaceae are a cosmopolitan family of flowering plants in the order Cornales. The family contains approximately 85 species in two genera, ''Alangium'' and ''Cornus''. They are mostly trees and shrubs, which may be deciduous or evergreen, alt ...
or
Nyssaceae
Nyssaceae is a family of flowering trees sometimes included in the dogwood family (Cornaceae). Nyssaceae is composed of 37 known species in the following five genera:Averyanov, L. V. & Hiep, N. T. (2002). ''Diplopanax vietnamensis'', a New Specie ...
. Its two known extant species inhabit the wet tropical mountains of
Vietnam
Vietnam or Viet Nam ( vi, Việt Nam, ), officially the Socialist Republic of Vietnam,., group="n" is a country in Southeast Asia, at the eastern edge of mainland Southeast Asia, with an area of and population of 96 million, making i ...
and southern China. They are broad-leaved evergreen trees with woody fruits and white or yellow flowers.
''Diplopanax'' was originally described from only one species, '' D. stachyanthus'', and placed in the family
Araliaceae
The Araliaceae are a family of flowering plants composed of about 43 genera and around 1500 species consisting of primarily woody plants and some herbaceous plants. The morphology of Araliaceae varies widely, but it is predominantly distinguish ...
, but this species was later discovered to be congeneric with '' Mastixicarpum'', a genus of flowering plants known only from fossils and assumed extinct since the
Pliocene
The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58Lazarus genus.) One additional species ('' D. vietnamensis'') was subsequently found and described.Averyanov, L. V. & Hiep, N. T. (2002). ''D. vietnamensis'', a New Species of Nyssaceae from Vietnam – One More Living Representative of the Tertiary Flora of Eurasia. ''Novon'' 12: 433-436. Availabl online (pdf) /ref>
Classification of ''Diplopanax'' is inconsistent due to ongoing investigation into its
phylogenetic
In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...
relationships. Although generally placed in Cornaceae, it has also been included in the family
Nyssaceae
Nyssaceae is a family of flowering trees sometimes included in the dogwood family (Cornaceae). Nyssaceae is composed of 37 known species in the following five genera:Averyanov, L. V. & Hiep, N. T. (2002). ''Diplopanax vietnamensis'', a New Specie ...
, when that family is removed from Cornaceae. ''Diplopanax'' is also sometimes separated, along with the genus ''Mastixia'', into the family Mastixiaceae.Fan, C. Z., and Xiang, Q. Y. (2003). Phylogenetic analyses of Cornales based on 26S rRNA and combined 26S rDNA-matK-rbcL sequence data. ''American Journal of Botany'' 90, 1357-1372.