Alternative names: Not Applicable

Description:
Evergreen trees or shrubs; leaves usually alternate or opposite, simple, entire, dotted with small resinous immersed glands and often aromatic, leathery or rigid; stipules 0 or rarely minute and caducous.

Flowers lateral, terminal or in umbels or panicles, bisexual, regular; sepals 4 or 5; petals 4 or 5, imbricate in bud but later spreading; in Eucalyptus the sepals and/or petals fused to form 1 or less often 2 opercula which is/are shed as the flowers open and neither sepals nor petals usually distinguishable; stamens 5 to numerous, inserted on a disk which may take the form of a thin erect free extension of the hypanthium or may form a prominent ring round the summit of the ovary; anthers usually dorsifixed and versatile; ovary inferior, 2-10-celled, with axile placentas or sometimes 1-celled, each placenta bearing 1 to several anatropous or campylotropous ovules; style short or less often long and bearded, with a small terminal stigma.

Fruit usually a capsule fused with the hypanthium and opening loculicidally at the apex, rarely succulent or an indehiscent nutlet; seeds without albumen; embryo straight or curved.

Distribution:  155 genera (75 in Australia and 45 in Central and South Americas) and about 3,000 species. (Johnson & Briggs in Morley & Toelken (1983) Flowering plants in Australia, pp. 175-185.)

Biology: No text

Taxonomic notes: All S.Aust. genera belong to subfamily Leptospermoideae. Subfamily Myrtoideae is mainly American and includes the European myrtle (Myrtus), the guavas (Psidium) and the Australian lilly-pilly (Eugenia).

Key to Genera:

1. Fruit a 3-10-celled capsule opening loculicidally at the apex in 3-10 valves
2. Perianth forming a circumscissile deciduous cap (calyptra) over the bud, sepals and petals not identifiable	EUCALYPTUS 5.
2. Petals and sepals distinguishable
3. Stamens longer than the petals
4. Stamens connate in 5 bundles	MELALEUCA 8.
4. Stamens free	CALLISTEMON 2.
3. Stamens shorter than the petals
5. Leaves opposite	BAECKEA 1.
5. Leaves alternate	LEPTOSPERMUM 7.
1. Fruit dry, indehiscent and l-celled or succulent
6. Fruit succulent	KUNZEA 6.
6. Fruit dry
7. Stamens c. 20	CALYTRIX 3.
7. Stamens 5 or 10
8. Style bearded toward the apex
9. Sepals entire, glabrous	DARWINIA 4.
9. Sepals fringed with long hairs	VERTICORDIA 11.
8. Style glabrous
10. Stamens 5 and opposite the petals or 10; ovules 4 or more, radical	MICROMYRTUS 9.
10. Stamens 5, opposite the sepals; ovules 2 or, if 4, superposed	THRYPTOMENE 10.

Author: Prepared by J.P. Jessop except where otherwise indicated