Description: Shrubs or small trees to c. 5 m high.
Leaves opposite, entire or (in two species) with irregular margins.
Inflorescences axillary triads or umbel-like dichasia, rarely of solitary flowers; the peduncles frequently 1.5–2 times longer than the flower stalks which are mostly slender; bracteoles clustered at the apex of the peduncle. Hypanthium more or less smooth; sepals simple or with some development of a dorsal lobe; stamens 7–14, located towards the margins of, or opposite, the sepals, geniculate.
Capsules 3-locular, thin-walled; seeds flattened, D-shaped, radially arranged on a protruding placenta.
Distribution and occurrence: A genus of 15 species: 11 in Australia (Victoria to north Queensland) and 4 in New Caledonia
Species in this genus were formerly included in Babingtonia but the latter genus is restricted to Western Australia. Apart from S. cunninghamii, all other species in N.S.W. were formerly included in a broadly defined Baeckea virgata or Babingtonia virgata. That species is a New Caledonian endemic and the name is no longer used for any Australian species.
Text by Peter G. Wilson
Taxon concept: Wilson et al. (2007) Aust. Syst. Bot. 20: 302–318.
| | Key to the species | |
| 1 | Margins of leaves crenate or conspicuously irregular | Sannantha cunninghamii |
| Margins of leaves entire or minutely and sharply toothed | 2 |
| 2 | Leaves >1.5 mm wide | 3 |
| Leaves <1.5 mm wide
Back to 1 | 5 |
| 3 | Leaves with midrib impressed on upper surface; 4-angular branchlets with undulating surface and crenate margins; inflorescences usually 3- or 7-flowered | Sannantha pluriflora |
| Leaves without midrib impressed on either surface; 4-angular branchlets smooth or papillose with entire margins; inflorescences mostly 7-flowered
Back to 2 | 4 |
| 4 | Leaves 1.7–2.5 mm wide; fruit c. 1.5 mm long; north from Dorrigo district | Sannantha collina |
| Leaves 2.5–3.5 mm wide; fruit 2.5–3 mm long; south from near Wollomombi Falls
Back to 3 | Sannantha crassa |
| 5 | Leaves ≤ 4 mm long | Sannantha whitei |
| Leaves >5 mm long
Back to 2 | 6 |
| 6 | Leaves 5.5–10 mm long and 0.5–1 mm wide, concolorous, plano-convex to concavo-convex; pedicels 1–3 mm long | Sannantha angusta |
| Leaves 7–15 mm long and 1.1–1.5 mm wide, discolorous, flat; pedicels 2.5–4 mm long
Back to 5 | Sannantha similis |
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