Syzygium pyrocarpum (Greves) Merr. & L.M.Perry

Craven, L. A., Damas, K. Q. & Cowley, K. J., 2021, Studies in Papuasian Syzygium (Myrtaceae): 2. The furfuraceous species of subg. Syzygium, Blumea 66 (1), pp. 57-81 : 76

31. Syzygium pyrocarpum (Greves) Merr. & L.M.Perry — Fig. 2 : 2.4; Map 8

Syzygium pyrocarpum (Greves) Merr. & L.M.Perry (1942) 280. — Eugenia pyrocarpa Greves (1923) 17. — Type: Forbes 99 (holo BM!; carbon rub- bing A n.v.), Papua New Guinea, Central Province, Sogeri, alt. c. 610 m, 20? Oct. 1885.

Eugenia xylantha Greves (1923) 18. — Syzygium xylanthum (Greves) Merr. & L.M.Perry (1942) 280. — Type: Forbes 325 (holo BM!), Papua New Guinea, Central Province, Sogeri, 30 Oct. 1885.

Tree to 21 m tall, to 20 cm dbh; outer bark grey-brown, inner bark brown, flaky. Vegetative branchlet quadrangular, angled, 5‒10 mm diam; bark dull, slightly striate, strongly glandular-verrucose, persistent. Leaf lamina broadly elliptic, broadly oblong, broadly ovate or sometimes broadly obovate, 20‒31.5 by 6.5‒16.5 cm, 1.9‒2.7 times as long as wide; base cuneate; apex acute to acuminate; acumen flat; margin flat; coriaceous; primary and secondary venation distinctly different with secondaries relatively little developed and not or rarely joining the intramarginal vein; primary veins 35‒48 on each side of the midrib, in median part of lamina at a divergence angle of 60‒70° and 5‒15 mm apart; intramarginal vein present, weakly arched, 2‒7 mm from margin, secondary intramarginal vein present. Petiole 2‒10 mm long. Reproductive seasonal growth unit with a reproductive zone only. Inflorescence leafless, cauline, paniculate, up to 10 by 5 cm, major axis 5‒6 mm thick at the midpoint, bark furfuraceous; bracts persistent; bracteoles subtending each flower, persistent. Flower buds with the apex rounded to obtuse. Flowers white, pink or brown (commonly recorded as pinkish brown, rarely as white). Hypanthium dull, furfuraceous, not visibly gland-dotted, plane but distinctly minutely wrinkled or ribbed, stipitate; very shortly goblet-shaped or broadly obconic, 7‒8 by 7‒9 mm, stipe c. 1 mm long. Calyx lobes 4, transversely semi-elliptic, c. 3 mm long. Petals 4, calyptrate (coherent and then falling as a cap). Staminal disc descending ( Fig. 2 : 2.4). Stamens 130‒140, 12‒18 mm long. Style c. 12 mm long. Placentation axile-basal; placenta a semispheroidal cushion. Ovules c. 18 per locule, ascending, arranged irregularly. Mature fruit red, furfuraceous, slightly ribbed, solid cup-shaped to astipitate goblet-shaped, c. 23 by 28 mm excluding the calyx, with the hypanthium rim appreciably expanding in fruit and 12 mm diam; seed subspheroid, c. 13 mm across, cotyledons collateral.

Distribution — Papua New Guinea.

Habitat & Ecology — Castanopsis -forest on ridge, rainforest on stony riverine terrace, lowland forest, wet flats in lower montane forest. Altitude 45‒1000 m.

Note — The large, broad leaves and congested inflores- cence are distinctive features of the species.

Figures

Fig. 2 Staminal disc types in Syzygium species. Series 1: Flat; series 2: descending; series 3: ascending; series 4: raised.