''Olearia microdisca'', commonly known as small-flowered daisy-bush, is a 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 ...

in the family

Asteraceae The family Asteraceae, alternatively Compositae, consists of over 32,000 known species of flowering plants in over 1,900 genera within the order Asterales. Commonly referred to as the aster, daisy, composite, or sunflower family, Compositae w ...

and is endemic to

Kangaroo Island Kangaroo Island, also known as Karta Pintingga (literally 'Island of the Dead' in the language of the Kaurna people), is Australia's third-largest island, after Tasmania and Melville Island. It lies in the state of South Australia, southwest ...

, South Australia. It is a compact shrub with small, crowded, oblong leaves and white and yellow, daisy-like

inflorescence An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed o ...

Description

''Olearia microdisca'' is a compact shrub that typically grows to a height of up to and has many softly-hairy branches. Its leaves are crowded, sometime overlapping each other, oblong long, about wide and

sessile Sessility, or sessile, may refer to: * Sessility (motility), organisms which are not able to move about * Sessility (botany), flowers or leaves that grow directly from the stem or peduncle of a plant * Sessility (medicine), tumors and polyps that ...

. The upper surface of the leaves is

glabrous Glabrousness (from the Latin ''glaber'' meaning "bald", "hairless", "shaved", "smooth") is the technical term for a lack of hair, down, setae, trichomes or other such covering. A glabrous surface may be a natural characteristic of all or part of ...

, the lower surface is woolly-hairy and the edges are rolled under. The heads or daisy-like "flowers" are arranged singly on the ends of erect branches and sessile. Each head has two to five white ray

florets This glossary of botanical terms is a list of definitions of terms and concepts relevant to botany and plants in general. Terms of plant morphology are included here as well as at the more specific Glossary of plant morphology and Glossary o ...

, the

ligule A ligule (from "strap", variant of ''lingula'', from ''lingua'' "tongue") is a thin outgrowth at the junction of leaf and leafstalk of many grasses (Poaceae) and sedges. A ligule is also a strap-shaped extension of the corolla, such as that of a ...

s about long, surrounding two or three yellow disc florets. Flowering occurs in most months and the fruit is a softly-hairy

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 ...

, the pappus about long with 25 to 35 bristles.

Taxonomy

''Olearia microdisca'' was first formally described in 1928 by

John McConnell Black John McConnell Black (28 April 1855 – 2 December 1951) was a Scottish botanist who emigrated to Australia in 1877 and eventually documented and illustrated thousands of flora in South Australia in the early 20th century. His publications assi ...

in ''

Transactions and Proceedings of the Royal Society of South Australia The Royal Society of South Australia (RSSA) is a learned society whose interest is in science, particularly, but not only, of South Australia. The major aim of the society is the promotion and diffusion of scientific knowledge, particularly in rel ...

''.

Distribution and habitat

Small-flowered daisy-bush grows in heath and mallee and is restricted to Kangaroo Island in South Australia.

Conservation status

''Olearia microdisca'' is listed as "endangered" under the Australian Government ''

Environment Protection and Biodiversity Conservation Act 1999 The ''Environment Protection and Biodiversity Conservation Act 1999'' (Cth) is an Act of the Parliament of Australia that provides a framework for protection of the Australian environment, including its biodiversity and its natural and cultu ...

''. A recovery plan for nationally threatened plant species on Kangaroo Island, including ''O. microdisca'', has been prepared.

References

{{Taxonbar, from= Q15587319 Asterales of Australia Flora of South Australia microdisca Plants described in 1928 Taxa named by John McConnell Black