''Olearia hectorii'' is a species of flowering plant in the daisy family Asteraceae. Its common names include deciduous tree daisy and Hector's tree daisy. It is endemic to New Zealand, where it is nationally endangered.

Taxonomy

Members of the genus ''Olearia'', commonly known as daisy-bushes or tree daisies, are found in New Zealand, Australia, and New Guinea. Although originally published under the name ''Olearia hectori'', ''hectorii'' is the correct epithet under the ICBN (ST Louis) Art. 60.11.

Description

''O. hectorii'' is a deciduous

shrub A shrub (often also called a 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 ...

or small tree, up to 10 m tall, with reddish stems, furrowed bark, and oppositely-arranged clusters of 2–4 gray-green leaves, 20–50 mm long by 5–20 mm wide. The undersides of the leaves are covered in a silvery indumentum. As with most other Asteraceae, the tiny flowers are borne in dense clusters known as pseudanthia, which are produced on short, hairy stems from near the leaf

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

. The florets are pale yellow, and enclosed by pale green, densely hairy phyllaries. The seeds are cypselae, similar in structure to those of dandelions, consisting of a 1–2 mm

achene An achene (; ), also sometimes called akene and occasionally achenium or achenocarp, is a type of simple dry fruit produced by many species of flowering plants. Achenes are monocarpellate (formed from one carpel) and indehiscent (they do not ope ...

attached to a 3–5 mm feathery pappus.

Ecology

This species is threatened by habitat degradation. It requires open habitat for germination, but this kind of habitat is threatened by introduced flora and grazing animals. ''Olearia hectorii'' is a host of numerous endemic moth species and is known to support at least 23 species, with at least 12 of those species exclusively hosted by this plant. These moths are likely to play an important role in the pollination of the ''O. hectorii''. Species dependent on this plant include the nationally critically endangered '' Stathmopoda campylocha'' and the nationally endangered ''S. albimaculata''.

Conservation status

This plant is now classified under the

New Zealand Threat Classification System The New Zealand Threat Classification System is used by the Department of Conservation to assess conservation priorities of species in New Zealand. The system was developed because the IUCN Red List, a similar conservation status system, had some ...

as being Nationally Endangered.

References

{{Taxonbar, from=Q7085998 hectorii Endangered flora of New Zealand Endemic flora of New Zealand Taxonomy articles created by Polbot Taxobox binomials not recognized by IUCN