Coleus argentatus (S.T.Blake) P.I.Forst. & T.C.Wilson APNI* Synonyms: Plectranthus argentatus S.T.Blake APNI*
Description: Erect to semi-erect, spreading suffrutescent subshrub to 0.6 m high, with a distinctively dense and silver indumentum of hairs (to 0.8 mm long) on branches and leaves. Coloured sessile multicellular glands 4-celled and orange. Branches with retrorse, densely distributed non-glandular hairs and densely distributed coloured sessile multicellular glands. Does not form a distinctive tuber. Lacking a strong scent when crushed.
Leaves concolorous, silver-green; petiole 4–35 mm long; lamina ovate, 30–80 mm long, 20–60 mm wide, margin serrate with 12–28 pairs of teeth, occasionally with 1 or more secondary teeth; upper surface veins impressed, with non-glandular and glandular hairs; lower surface veins raised, non-glandular hairs up to 0.8 mm long, coloured sessile multicellular glands sparsely to densely distributed.
Inflorescence to 190 mm high, consisting of up to 3 racemose branches 30–180 mm long; verticillasters 6–10-flowered. Pedicel 2.6–5.0 mm long. Calyx 2.4–3.4 mm long. Corolla white to very pale lilac, 5–10 mm long; tube 3.5–5.1 mm long, ± straight (curved downwards at an angle of 0°–10°). Style slightly longer than stamen, not extending to sometimes barely extending past lower corolla lobe.
Fruiting calyx accrescent, 3.7–4.1 mm long. Mericarp semi-spherical, 1.0–1.1 mm long, 0.8– 0.9 mm wide.
Flowering: typically between November to May.
Distribution and occurrence: Occurs in a restricted area of north-eastern New South Wales adjacent to the border ranges area of Queensland. Uncommon, grows on rock outcrops and on exposed cliffs along rainforest margins at altitudes above 800 m.
NSW subdivisions: NC
Other Australian states: Qld
One of the most distinctive Coleus in Australia due to its unmistakeably silver indumentum. Can be distinguished from other NSW species by its 4-celled sessile glands on stems and leaves (vs. only 8-celled sessile glands), and all but C. nitidus by its corolla with a ± straight tube (vs. tube bent at least ~25°). Commonly cultivated.
Text by T.C.Wilson (April 2026)
Taxon concept: Paton A.J. (2019) Nomenclatural changes in Coleus and Plectranthus(Lamiaceae): a tale of more than two genera. PhytoKeys 129:1–158.
APNI* Provides a link to the Australian Plant Name Index (hosted by the Australian National Botanic Gardens) for comprehensive bibliographic data
***The AVH map option provides a detailed interactive Australia wide distribution map drawn from collections held by all major Australian herbaria participating in the Australian Virtual Herbarium project.
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