Melaleuca tuberculata

Melaleuca tuberculata is a small, variable shrub in the myrtle family Myrtaceae and is endemic to the south-west of Western Australia. There are three distinct varieties of this species, each with a different leaf size and shape, different distributions and somewhat different habitat preferences.

Melaleuca tuberculata
M. tuberculata (leaves, flowers, fruit)
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Rosids
Order:	Myrtales
Family:	Myrtaceae
Genus:	Melaleuca
Species:	M. tuberculata
Binomial name
Melaleuca tuberculata Schauer

Description

Melaleuca tuberculata grows to a height of 0.2–2 m (0.7–7 ft). Its leaves are arranged alternately, 2–19 mm (0.08–0.7 in) long, 0.8–3.5 mm (0.03–0.1 in) wide and are linear to narrow oval in shape.

The flowers are arranged in heads up to 25 mm (1 in) in diameter, at or near the ends of the branches, with one to seven groups of flowers, each with three individual flowers. There are hairy brown bracts at the base of the flowers and the flower buds are covered with white, woolly hairs. The flowers appear from August to December, varying slightly with each variety, and are pale to mid-pink or mauve. The stamens are arranged in bundles of five around the flower, with six to ten stamens in each bundle, the bright yellow anthers contrasting with the mauve filaments. The cup-shaped base of the flower (the hypanthium) is hairy and 1.5–3 millimetres (0.06–0.1 in) long. The woody capsules are 3–4 mm (0.1–0.2 in) long and wide.[1][2]

The three varieties can be distinguished on the basis of the sizes of their leaves:[2]

• var. arenia - 2–4.2 mm (0.08–0.2 in) long, 1.1–2.3 mm (0.04–0.09 in) wide;
• var. macrophylla - 4.5–18.5 mm (0.2–0.7 in) long, 1.2–3.5 mm (0.05–0.1 in) wide;
• var. tuberculata - 2.5–13.5 mm (0.1–0.5 in) long, 0.8–1.3 mm (0.03–0.05 in) wide.

M. tuberculata growing 50 km west of Esperance

Taxonomy and naming

Melaleuca tuberculata was first formally described in 1844 by Johannes Conrad Schauer in Plantae Preissianae.[3][4] The specific epithet (tuberculata) is derived from the Latin word meaning "full of lumps"[5] "in reference to the prominent oil glands on the leaves".[2]

Distribution and habitat

Melaleuca tuberculata occurs in the Avon Wheatbelt, Esperance Plains, Jarrah Forest and Mallee biogeographic regions.[6] It grows in a variety of soils over ironstone or laterite, on undulating plains and high areas.[7]

The distribution of the varieties is as follows:[2]

• var. arenia - the Bendering–Kulin–Hyden–Pingaring district;
• var. macrophylla - from the Kulin–Jerramungup district eastwards to the Grass Patch – Israelite Bay district.
• var. tuberculata - Brookton–Narrogin district eastwards to the Esperance – Israelite Bay district.

Conservation

This species is classified as "not threatened" by the Government of Western Australia Department of Parks and Wildlife.[6]

References

1. Holliday, Ivan (2004). Melaleucas : a field and garden guide (2nd ed.). Frenchs Forest, N.S.W.: Reed New Holland Publishers. pp. 298–299. ISBN 1876334983.
2. Brophy, Joseph J.; Craven, Lyndley A.; Doran, John C. (2013). Melaleucas : their botany, essential oils and uses. Canberra: Australian Centre for International Agricultural Research. pp. 368–369. ISBN 9781922137517.
3. "Melaleuca tuberculata". APNI. Retrieved 12 March 2015.
4. Lehmann, J.G.C. (1844). Plantae Preissianae. Hamburg. p. 139.
5. Brown, Roland Wilbur (1956). The Composition of Scientific Words. Washington, D.C.: Smithsonian Institution Press. p. 774.
6. "Melaleuca tuberculata". FloraBase. Western Australian Government Department of Parks and Wildlife.
7. Paczkowska, Grazyna; Chapman, Alex R. (2000). The Western Australian flora : a descriptive catalogue. Perth: Wildflower Society of Western Australia. p. 398. ISBN 0646402439.