''Broussaisia arguta'', the kanawao, is a species of

perennial In horticulture, the term perennial ('' per-'' + '' -ennial'', "through the year") is used to differentiate a plant from shorter-lived annuals and biennials. It has thus been defined as a plant that lives more than 2 years. The term is also ...

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (). The term angiosperm is derived from the Ancient Greek, Greek words (; 'container, vessel') and (; 'seed'), meaning that the seeds are enclosed with ...

in the ''

Hydrangea ''Hydrangea'' ( or ) is a genus of more than 70 species of Flowering plant, flowering plants native plant, native to Asia and the Americas. Hydrangea is also used as the common name for the genus; some (particularly ''Hydrangea macrophylla, H. m ...

'' family,

Hydrangeaceae Hydrangeaceae is a family of flowering plants in the order Cornales, with a wide distribution in Asia and North America, and locally in southeastern Europe. Description The genera are characterised by leaves in opposite pairs (rarely whorled or ...

, that is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

Hawaii Hawaii ( ; ) is an island U.S. state, state of the United States, in the Pacific Ocean about southwest of the U.S. mainland. One of the two Non-contiguous United States, non-contiguous U.S. states (along with Alaska), it is the only sta ...

. It is the only species in the monotypic genus ''Broussaisia''. Kanawao is a widespread species occurring in mesic and wet forests on all of the main

Hawaiian Islands The Hawaiian Islands () are an archipelago of eight major volcanic islands, several atolls, and numerous smaller islets in the Pacific Ocean, North Pacific Ocean, extending some from the Hawaii (island), island of Hawaii in the south to nort ...

. It is a

dioecious Dioecy ( ; ; adj. dioecious, ) is a characteristic of certain species that have distinct unisexual individuals, each producing either male or female gametes, either directly (in animals) or indirectly (in seed plants). Dioecious reproduction is ...

evergreen In botany, an evergreen is a plant which has Leaf, foliage that remains green and functional throughout the year. This contrasts with deciduous plants, which lose their foliage completely during the winter or dry season. Consisting of many diffe ...

plant that either grows as a

shrub A shrub or bush is a small to medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees by their multiple ...

or a

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, e.g., including only woody plants with secondary growth, only ...

. The obovate

leaves A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, ...

are long and wide with finely serrated margins. Relationship to other Organisms The ''Orthotylus broussaisia'' (''O. broussaisiae'') from Kauai feeds on ''Broussaisia arguta''. Although there has been extensive research on ''Broussaisia arguta'', only the ''Orthotylus broussaisiae'' species has been found feeding on it.

References

Hydrangeaceae Cornales genera Trees of Hawaii Endemic flora of Hawaii Monotypic asterid genera Dioecious plants Flora without expected TNC conservation status {{tree-stub