Polyosma schulzemenzii 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 : 83-84

28. Polyosma schulzemenzii B.J.Conn & O.K.Paul , sp. nov. — Fig. 14

Etymology. The specific epithet of this new species commemorates Dr. Georg K. Schulze-Menz, a former director of the Botanical Garden and Botanical Museum Berlin-Dahlem (B), whose revision of the Polyosma in the Indonesian-Melanesian-Australian region was not completed because of his sudden death in 1978 ( Potztal 1979). Unfortunately, his manuscript of the genus Polyosma was not publishable. Although Schulze-Menz recognised this entity as a new species (by the unpublished manuscript name ‘ Polyosma perlongibracteolata ’), we decided that the similarity of his proposed specific epithet with that of P. longebracteolata could have resulted in nomenclatural confusion. Furthermore, we wished to acknowledge Schulze-Menz’s exten- sive research into the taxonomy of this genus by naming this species after him.

Polyosma schulzemenzii is morphologically most similar to P.pubescens , but it differs by its obovate leaf lamina which has a rounded base (vs elliptic leaves with acute base for P. pubescens ). It has larger flowers (corolla 10–20 mm long, greenish brown) than those of P. pubescens (vs corolla 5–10 mm long, pinkish green). — Type: L.J. Brass 31168 (holo L [L 0035111]; iso K, LAE [ LAE 40014]), Papua New Guinea, Eastern Highlands, western slopes of Mt Michael , 27 Aug. 1959.

Subcanopy tree, c. 12 m tall. Branchlets hairy, brown, ridged. Leaves: petiole 1–2 cm long, hairy, brown; lamina narrowly obovate, 7–12 by 2–3.5 cm, coriaceous, densely hairy, abaxial surface ferruginous, drying brown on both surfaces; base rounded, margin entire, apex attenuate; secondary veins 17–19 on each side of midrib and at an angle greater than 45° from midrib, looping near margin onto the next secondary vein; tertiary veins weakly percurrent, prominent on abaxial surface, pubescent. Inflorescence racemose, terminal, 20–30-flowered; rachis 5–13 cm long, densely hairy; flowers loosely and evenly scattered along length of rachis; pedicels 2–4 mm long; bracteoles 5–10 mm long, hairy. Calyx lobes 5–10 mm long. Corolla buds tubular, (10–) 14–20 mm long, brown, with greenish tinge; corolla densely hairy, remaining tubular at anthesis, except opening with 4 small lobes distally. Fruits not seen.

Distribution — Papua New Guinea (West Sepik, Morobe, Eastern Highlands).

Habitat & Ecology — Occurring in lowland montane forest dominated by Castanopsis (D.Don) Spach ( Fagaceae ) species at elevations of about 1 890 m.

Conservation status — This species is inadequately sampled. Therefore, even though it appears to be widespread, its conservation status is not known.

Additional specimens examined (Paratypes). PAPUA NEW GUINEA, West Sepik, Amanab-Green River Road, H. Streimann & N. Martin LAE 52850 (BRI, L, LAE ); Morobe, Edie Creek, Wau, T.G. Hartley 11739 ( LAE ).

Notes — 1. The mature open corolla of P. schulzemenzii remains tubular with only a small opening apically, whereas the mature corolla of P. pubescens splits to the base so that there is no remaining colour tube (style clearly exposed).

2. Polyosma schulzemenzii has leaves that are densely hairy and ferruginous on the abaxial surface, similar to those of P. brassii . However, the leaf lamina of this new species is narrowly obovate whereas those of P. brassii are elliptic. Like P. longebracteolata , this new species has bracteoles that are as long as the calyx; however, P. schulzemenzii is readily distinguished by its petioles 1–2 cm long, leaf lamina 7–12 cm long, and inflorescences 5–13 cm long (vs P. longebracteolata with petiole 0.4–0.8 cm long, leaf lamina (1–) 2–5 cm long, and inflorescences 3–3.5 cm long).

Figures

Fig. 14 Holotype collection of Polyosma schulzemenzii B.J.Conn & O.K.Paul (L.J. Brass 31168 [L 0035111]).