Polyosma pubescens Ridl.

26. Polyosma pubescens Ridl. View in CoL

Polyosma pubescens Ridl. (1916) View in CoL 38. — Lectotype (designated here): C. Boden Kloss s.n. (lecto BM [BM600388];isolecto K), Indonesia, Papua, Mimika, Camp I (c. 4.5 miles from Setakwa River, eastern tributary of the Utakwa River (Boden Kloss in Ridley 1916, Ballard 2001), ( 18–20 Sept. 1912 ( Ridley 1916)) (see Typification below).

Typification — The only type information provided by Ridley (1916) was the locality information ‘Camp I, 500 ft. ’ Therefore, the Boden Kloss s.n. collection as held at BM [ BM600388 ], is here designated as the lectotype because it was collected from ‘Camp I’, with the isolectotype held at K .

Subcanopy tree, 6–10 m tall. Branchlets pubescent, smooth, brown. Leaves sparsely hairy;petiole 0.8–1.5 cm long,pale brown; lamina elliptic, 9–11 by 3.5–4.5 cm, coriaceous, drying brown on both surfaces; base acute, margin entire, apex attenuate; secondary veins 10–15 on each side of midrib and at an angle greater than 45° from midrib, looping near margin onto the next secondary vein; tertiary vein weakly percurrent, prominent on abaxial surface, sparsely hairy. Inflorescence racemose, either axillary or terminal,> 30-flowered; rachis 10–10.5 cm long, sparsely pubescent; pedicels 3–4 mm long; bracteoles 2–5 mm long, sparsely hairy. Calyx lobes 1–2 mm long. Corolla buds tubular, 10–15 mm long, pinkish green to purplish; corolla densely hairy, fully split at anthesis. Fruits not seen.

Distribution — Indonesia ( Papua) and Papua New Guinea ( Milne Bay). The distribution of this species is very inadequately known. It is most unlikely that it only occurs in two localities that are at opposite ends of the island of New Guinea.

Habitat & Ecology — Occurring in lower montane forest at elevations of about 1 350 m, recorded from Araucaria - Lithocarpus ridge forest in Milne Bay ( Stevens LAE 55753).

Conservation status — Not known: this species is undercollected, and hence, its distribution and habitat preferences are inadequately known.

Additional specimen examined. PAPUA NEW GUINEA, Milne Bay,Raba Raba, Mt Suckling, P.F. Stevens & J.­F. Veldkamp LAE 55753 (L, LAE, NSW ).

Notes — 1. This species is similar to P. induta , but P. pubescens has leaves with an entire margin, whereas the leaf margin of P. induta is serrate.

2. Polyosma induta is morphologically most like P. forbesii , which also has a serrate leaf margin. Many features of P. pubescens are also like P. forbesii , apart from the leaf margin. However, P. pubescens is a small tree ( 6–10 m tall vs P. forbesii 10–20 m tall) and is sparsely hairy, whereas P. forbesii is densely hairy. This suggests that the taxonomic importance of the presence or absence of marginal teeth, on the leaf margin, requires further evaluation.

3. Although P. pubescens is morphologically like P. schulzemenzii , they were consistently distinguished from each other in our cluster analysis ( Fig. 1 View Fig ) and in the SSH-MST analysis ( Fig. 2 View Fig ). Therefore, they are maintained as two distinct species. Polyosma pubescens has smooth branchlets and leaves with petiole 0.8–1.5 cm long (whereas P. schulzemenzii has ridged branchlets and leaves with mostly longer petioles, 1–2 cm long); P. pubescens has a broader elliptic lamina, 3.5–4.5 cm wide, with base acute, and secondary veins 10–15 on each side of midrib (vs P. schulzemenzii has narrowly obovate leaves, 2–3.5 cm wide, with base rounded, and secondary veins 17–19 on each side of midrib); the inflorescences of P. pubescens are either axillary or terminal, with the rachis sparsely pubescent (vs P. schulzemenzii has only terminal inflorescences and the rachis densely hairy); P. pubescens has shorter bracteoles ( 2–5 mm long); and smaller flowers ( calyx lobes 1–2 mm long; corolla 5–10 mm long), compared to P. schulzemenzii that has bracteoles 5–10 mm long, calyx lobes 5–10 mm long, and corolla 10–20 mm long.