''Melaleuca ordinifolia'' is a plant in the myrtle family,

Myrtaceae Myrtaceae, the myrtle family, is a family of dicotyledonous plants placed within the order Myrtales. Myrtle, pōhutukawa, bay rum tree, clove, guava, acca (feijoa), allspice, and eucalyptus are some notable members of this group. All speci ...

, and is endemic to the

south-west The points of the compass are a set of horizontal, radially arrayed compass directions (or azimuths) used in navigation and cartography. A compass rose is primarily composed of four cardinal directions—north, east, south, and west—each se ...

of Western Australia. It is closely related to '' Melaleuca brevifolia'', but is smaller and differing mainly in its leaf features.

Description

''Melaleuca ordinifolia'' is a shrub to about tall. Its leaves are crowded together, and arranged in alternating pairs (

decussate Decussation is used in biological contexts to describe a crossing (due to the shape of the Roman numeral for ten, an uppercase 'X' (), ). In Latin anatomical terms, the form is used, e.g. . Similarly, the anatomical term chiasma is named aft ...

), so that they are in four rows along the branchlets. Each leaf is long and wide, very narrow oval in shape, slightly dished and with a rounded end. This species flowers profusely with many heads of white flowers on the sides of the branches. Each head is up to in diameter and contains one to six individual flowers. The

stamen The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filame ...

s are arranged in five bundles around the flowers and there are 8 to 12 stamens per bundle. The main flowering period is in early spring and is followed by fruit which are woody capsules long.

Taxonomy and naming

''Melaleuca ordinifolia'' was first formally described in 1992 by Bryan Barlow in Nuytsia as a new species. The

specific epithet In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

(''ordinifolia'') is from the Latin ''ordo'' meaning a "methodical arrangement", "line", "series" or "row" and ''folium'' meaning "a leaf" referring to the regular arrangement of the leaves.

Distribution and habitat

''Melaleuca ordinifolia'' is confined to the

Stirling Range The Stirling Range or Koikyennuruff is a range of mountains and hills in the Great Southern region of Western Australia, south-east of Perth. It is over wide from west to east, stretching from the highway between Mount Barker and Cranb ...

and

Hamersley River The Hamersley River is an ephemeral river in the Great Southern region of Western Australia. The headwaters of the river rise east of Fitzgerald and just north of the South Coast Highway on an undulating sandplain on the edge of the Yilgarn ...

districts in the Avon Wheatbelt, Esperance Plains, Jarrah Forest and Mallee

biogeographic regions A biogeographic realm or ecozone is the broadest biogeographic division of Earth's land surface, based on distributional patterns of terrestrial organisms. They are subdivided into bioregions, which are further subdivided into ecoregions. De ...

growing in sandy loam or clay.

Conservation

This species is classified as " Priority Two" by the

Government of Western Australia The Government of Western Australia, formally referred to as His Majesty's Government of Western Australia, is the Australian state democratic administrative authority of Western Australia. It is also commonly referred to as the WA Government o ...

Department of Parks and Wildlife The Department of Parks and Wildlife (DPaW) was the department of the Government of Western Australia responsible for managing lands described in the ''Conservation and Land Management Act 1984'' and implementing the state's conservation and e ...

meaning that is poorly known and from one or a few locations.

References

{{Taxonbar, from=Q15372602 ordinifolia Myrtales of Australia Plants described in 1992 Endemic flora of Western Australia