Coprosma J.R.Forst. & G.Forst.

Timothy M. A. Utteridge and Laura V. S. Jennings (2022). Trees of New Guinea. Kew Publishing. Royal Botanic Gardens, Kew

Distribution

A genus of c. 120 species with a distribution from Java through to New Guinea and the Solomon Islands, Australia and New Zealand to Macquarie Island and the Pacific to Hawaii. Notably absent from New Caledonia. At least seven species occur in New Guinea, and with a single, endemic species Coprosma bougainvilleensis Gideon in the Solomon Islands.

Morphology General Habit

Epiphytes, shrubs or shrubby trees to 6 m, sometimes scrambling or cushion-forming; bark often papery and splitting (in New Guinea), pale grey- or ginger-brown to black in colour, branches often swollen at nodes

Morphology General

Raphides present

Morphology Leaves Stipules

Stipule margins entire to fimbriate, often woody and drying pale, margins often glandular

Morphology Leaves

Leaves subsessile or shortly petiolate and sometimes in whorls of 3, with domatia, discolorous, foetid (rarely fragrant) when crushed

Morphology Reproductive morphology Inflorescences

Inflorescence few flowered or solitary, usually terminal-Flowers usually unisexual and plants dioecious; (3–)4–5(–10)-merous; calyx present or absent; corolla valvate in bud, colour variable from light green to dark purple-brown, campanulate to funnel-shaped; stamens and styles often well exserted and pendulous, styles free to base; ovary 2(–3–4)-locular, 1 ovule per locule

Morphology Reproductive morphology Fruits

Fruit an orange, red or purple-black fleshy drupe with 2(–3–4) 1-seeded pyrenes.

Ecology

Species in New Guinea are only known from montane to alpine regions, and are found in grass-, fern- and heath-lands (including fire induced vegetation), bogs and subalpine forest and edges, to c. 4000 m.

Recognition

A distinctive wind pollinated genus which may be identified by the foetid odour of crushed parts, distinctive branches and the often woody-fimbriate stipules. The exserted stigmas or anthers which look disproportionately large in comparison to the flowers and/or leaves may also be useful in some species.