Hydrangeaceae is a

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

of flowering plants in the order

Cornales The Cornales are an order of flowering plants, early diverging among the asterids, containing about 600 species. Plants within the Cornales usually have four-parted flowers, drupaceous fruits, and inferior to half-inferior gynoecia topped with ...

, with a wide distribution in Asia and North America, and locally in southeastern

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...

Description

The genera are characterised by

leaves A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", wh ...

in opposite pairs (rarely whorled or alternate), and regular, bisexual

flower 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 mechani ...

s with 4 (rarely 5–12) petals. The

fruit In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering. Fruits are the means by which flowering plants (also known as angiosperms) disseminate their seeds. Edible fruits in particu ...

is a capsule or

berry A berry is a small, pulpy, and often edible fruit. Typically, berries are juicy, rounded, brightly colored, sweet, sour or tart, and do not have a stone or pit, although many pips or seeds may be present. Common examples are strawberries, raspb ...

containing several

seed A seed is an embryonic plant enclosed in a protective outer covering, along with a food reserve. The formation of the seed is a part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiospe ...

s, the seeds with a fleshy

endosperm The endosperm is a tissue produced inside the seeds of most of the flowering plants following double fertilization. It is triploid (meaning three chromosome sets per nucleus) in most species, which may be auxin-driven. It surrounds the embryo and ...

Genera

The following genera are accepted: *'' Carpenteria'' Torr. *''

Deutzia ''Deutzia'' ( or ) is a genus of about 60 species of flowering plants in the family Hydrangeaceae, native to eastern and central Asia (from the Himalayas east to Japan and the Philippines), and Central America and also Europe. By far the highest ...

'' Thunb. *''

Fendlera ''Fendlera'' is a genus of shrubs in the Hydrangeaceae. They are most commonly known as fendlerbush. The name fendlerbush is also used for the closely related genus ''Fendlerella''. The genus was named for Augustus Fendler in 1852.in Smithson. C ...

'' Engelm. & A.Gray *''

Fendlerella ''Fendlerella'' is a monotypic genus of shrubs in the Hydrangeaceae containing the single species ''Fendlerella utahensis''. This plant is known as Utah fendlerella, yerba desierto, or sometimes as Utah fendlerbush (it having previously been incl ...

'' A.Heller *''

Hydrangea ''Hydrangea'', () commonly named the hortensia, is a genus of over 75 species of flowering plants native to Asia and the Americas. By far the greatest species diversity is in eastern Asia, notably China, Korea, and Japan. Most are shrubs tall, ...

'' Gronov. ex L. *'' Jamesia'' Torr. & A.Gray *'' Kirengeshoma'' Yatabe *''

Philadelphus ''Philadelphus'' () (mock-orange) is a genus of about 60 species of shrubs from 3–20 ft (1–6 m) tall, native to North America, Central America, Asia and (locally) in southeast Europe. They are named "mock-orange" in reference to their ...

'' L. *''

Whipplea ''Whipplea'' is a monotypic genus containing the single species ''Whipplea modesta'', which is known by several common names including common whipplea, yerba de selva, and modesty. It is a dicot shrub or sub-shrub in the Hydrangeaceae family, nat ...

'' Torr.

Phylogeny

The family Hydrangeaceae has two subfamilies, namely Jamesioideae and Hydrangeoideae. The subfamily Jamesioideae comprises the genera Jamesia and Fendlera.Kim, C., Deng, T., Wen, J., Nie, Z. L., & Sun, H. (2015)
"Systematics, biogeography, and character evolution of Deutzia (Hydrangeaceae) inferred from nuclear and chloroplast DNA sequences."
Molecular Phylogenetics and Evolution, 87, 91-104. They are the sister group to the remaining Hydrangeaceae.Kubitzki, K. (2013)
"Flowering Plants. Dicotyledons: Celastrales, Oxalidales, Rosales, Cornales, Ericales."
p. 206. Springer Berlin Heidelberg. The subfamily Hydrangeoideae has two tribes: Hydrangeae consists of Hydrangea s.l.,Samain, M. S., Wanke, S., & Goetghebeur, P. (2010)
"Unraveling extensive paraphyly in the genus ''Hydrangea'' s.l. with implications for the systematics of tribe Hydrangeeae."
Systematic Botany, 35(3), 593-600. and Philadelpheae consists of ''Philadelphus'', ''Carpenteria'', ''Deutzia'', ''Kirengeshoma'', ''Whipplea'', and ''Fendlerella''.Hufford, L., Moody, M. L., & Soltis, D. E. (2001)
"A phylogenetic analysis of Hydrangeaceae based on sequences of the plastid gene matK and their combination with rbcL and morphological data."
International Journal of Plant Sciences, 162(4), 835-846. ''Carpenteria'' is the sister group to ''Philadelphus''. ''Deutzia'' is the sister group to ''Kirengeshoma'', and ''Fendlerella'' is the sister group to ''Whipplea''. However the relationships among those three clades within the tribe Philadelphae are a bit unclear. The following cladogram summarizes results from different studies, and for each node it is noted which studies support the sister group positions of the following branches:

References

Asterid families {{Cornales-stub