Polyosma brassii Schulze-Menz ex B.J.Conn & O.K.Paul, 2024

Paul, O. K., Conn, B. J. & Henwood, M. J., 2024, Taxonomic review of Polyosma (Escalloniaceae) in Papuasia, Blumea 69, pp. 54-88 : 67-68

4. Polyosma brassii Schulze-Menz ex B.J.Conn & O.K.Paul , sp. nov. — Fig. 6

Etymology. The specific epithet acknowledges the Australian botanical collector Leonard J. Brass ( Perry 1971), who collected extensively throughout New Guinea and discovered this new species.

Polyosma brassii is morphologically most like P. induta and P. helicioides . Even though all three species have elliptic leaves, being broadly elliptic in P. induta , it differs from the latter two species by having an acuminate leaf apex (vs attenuate in P. induta and P. helicioides ) and flowers with corolla brown (vs greenish white or yellow for the latter two species). — Type: L.J. Brass 29597 (holo LAE [ LAE 34056]);iso L [L0035074]), Papua New Guinea, Morobe, Mt Kaindi, 15 May 1959.

Tree, 8–15 m tall. Branchlets densely hairy, brown, moderately angular or ridged. Leaves densely hairy; petiole 1–5 cm long,

brown; lamina elliptic, 6–14 by 3–6 cm, coriaceous, drying dark brown on both surfaces; base acute to cuneate, margin serrate, apex acuminate; secondary veins 12–19 on each side and at an angle greater than 45° from midrib, regularly looping near margin onto the next secondary vein; tertiary veins weakly percurrent, pubescent, prominent on abaxial surface. Inflorescence racemose, axillary, 20–30-flowered; rachis 6–8 cm long, densely hairy; flowers loosely and evenly arranged (not clustered); pedicels 8–12 mm long; bracteoles 1–2 mm long, densely hairy. Calyx lobes 1–3 mm long. Corolla buds tubular, (10–) 12–20 mm long, brown, with yellowish tinge; corolla densely hairy, remaining tubular at anthesis, except opening with 4 small lobes distally. Fruits ovoid, 9–13 by 5–8 mm, hairy, green.

Distribution — Papua New Guinea (Morobe Prov.: Wau, Mt Kaindi).

Habitat & Ecology — Occurring in mid montane Nothofagus forest ( Nothofagaceae ) between elevations of 1 800–2 200 m.

Conservation status — This species is only known from Mt Kaindi in the Morobe Province. This is an area that is continu- ing to be adversely affected by clearing and other anthropogenic disturbances. Therefore, it is suspected that this species is endangered.

Additional specimens examined (Paratypes). PAPUA NEW GUINEA, Morobe Province, Mt Kaindi, Wau , T . G . Hartley 11739 ( K, L); ibid., J . L .C. H. van Valkenburg 764 (seedling) (L).

Notes — 1. Polyosma brassii and P. helicioides are morphologically similar by having axillary inflorescences (vs terminal in P. induta ). Polyosma brassii and P. induta have hairy branchlets, leaves and fruits, whereas P. helicioides has glabrous or slightly hairy branchlets and leaves, with fruits glabrous.

2. The branchlets and leaves of P. brassii , P. forbesii , and P. schulzemenzii are densely ferruginous with dark rusty brown hairs; however, this species differs from P. forbesii with its acuminate leaf apex (vs attenuate in P. forbesii ); bracteoles usually shorter (1–2 mm long vs 1–10 mm long in P. forbesii ); and brown corolla (vs yellowish green in P. forbesii ). Polyosma brassii has elliptic leaves and hence differs from the narrowly obovate leaves of P. schulzemenzii .

Figures

Fig. 6 Isotype collection of Polyosma brassii Schulze-Menz ex B.J.Conn & O.K.Paul (L.J. Brass 29597 [L 0035074]).