Prostanthera melissifolia F.Muell. - Lamiaceae - balm mint bush

Erect shrub to small tree, 1-2(-5)m high, native to Australia (Victoria); branches 4-ridged; leaves ovate, margins toothed, dark-green above, paler below, slightly and faintly unpleasantly aromatic, densely glandular, petiole (8-)10-15mm long; inflorescence 10-20-flowered; corolla 10-12mm long, dark mauve, occasionally pinkish.
[Conn, Barry J. „Contributions to the systematics of Prostanthera (Labiatae) in south-eastern Australia.“ Telopea 7.4 (1998): 319-331]
"Prostanthera melissifolia F.Muell". Flora of Victoria. Royal Botanic Gardens Victoria, Australia. Retrieved 2017-11-23.
"Prostanthera melissifolia F.Muell". PlantNET - New South Wales Flora Online. Royal Botanic Gardens & Domain Trust, Sydney Australia. Retrieved 2017-11-23.

The essential oil of Prostanthera melissifolia provided at least some protection against 3 mosquito species, with the longest protection time (110 min) against Culex quinquefasciatus.
[Maguranyi, Suzann K., et al. „Are commercially available essential oils from Australian native plants repellent to mosquitoes?.“ Journal of the American Mosquito Control Association 25.3 (2009): 292-300]

Main components of a commercial oil with odour characteristics „rich mint aroma with crisp eucalyptus notes“ were piperitone (33.6%), 1.8-cineole (22.5%), α-pinene (17.8%), linalool (14.2%), and terpinen-4-ol (3.6%).
"Balm Mint Bush Essential Oil" Plant Therapy Inc. GC/MS provided by phytotherapia.com, retrieved 2017-11-22.

Prostanthera melissifolia, author: Jimbo1199, (2003) wikimedia commons, © Public Domain