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Synonyms: Plectranthus nitidus P.I.Forst. APNI*

Description: Semi-erect, open branched herb to 0.4 m tall with a distinctively shiny surface on leaves and stem. Lacking a strong scent when crushed. Sessile multicellular glands 4- to 8-celled and yellow to orange. Branches sparsely covered by appressed (usually antrorse) non-glandular trichomes. Does not form a distinctive tuber.

Leaves discolorous; petiole 11–30 mm long; lamina narrow-ovate or ovate, 25–55 mm long, 15–35 mm wide, margin serrate with 6–8 pairs of teeth (occasionally with 1 or more secondary teeth); upper surface green or purplish green, veins impressed, glabrous; lower surface reddish purple, veins raised, sessile multicellular glands sparse.

Inflorescence 200–400 mm long, with up to 3(–5) racemose branches, verticillasters 6–10-flowered. Pedicel 4–6.3 mm long. Calyx 2.5–2.7 mm long. Corolla white to rarely very pale bluish mauve, lateral lobes and base of adaxial lobes bluish mauve, white along midvein of lateral lobes, 8–9 mm long; tube 3.8–4.4 mm long, curved downwards at a maximum angle of 25°–30°. Stamen 7.5–9.6 mm long, not extending past lower corolla lobe, pollen white. Style 7–9 mm long, extending past stamen but only slightly past lower corolla lobe.

Fruiting calyx accrescent, 3.6–3.8 mm long. Mericarp glossy black, circular in outline, flattened, 0.9–1 mm long, 0.5–0.8 wide, 0.7–0.9 mm long and wide.

Type Specimen

Flowering: from October to January.

Distribution and occurrence: Distributed along southeastern Australian, from Barrington Tops National Park north to Mt Glorious, Queensland.

Grows on rock outcrops or steep slopes in rainforest, or open wet sclerophyll forest adjacent to rainforest.
NSW subdivisions: NC, NT
Other Australian states: Qld

AVH map***

This species is considered endangered by Saving our Species (SoS, Office of Environment & Heritage NSW) and under the EPBC Act. The overall habit and shiny leaves are similar to C. apreptus of northern Queensland, which, on account of misidentifying C. nitidus, was thought to have previously occurred in New South Wales. It appears most closely related to C. australis, largely due to similarities in general habit, inflorescence, and a weakly curved corolla tube. Coleus nitidus differs from C. australis because it lacks glandular trichomes, a distinctively swollen tuberous base, and scent. The two may be found nearby, and unpublished evidence from DNA sequence demonstrates they are capable of hybridising. The corolla tube is more straight than that of C. australis, much like C. argentatus. A more robust, shrubby species with similar flowers that occurs in New England National Park might be a hybrid between a more shrubby species and it, or C. argentatus.