Syzygium thornei T.G.Hartley & 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 : 79-80

39. Syzygium thornei T.G.Hartley & L.M.Perry — Fig. 2 : 1.6; Map 10

Syzygium thornei T.G.Hartley & L.M.Perry (1973) 206. — Type: NGF (Gray & Thorne) 12899 (holo A n.v.; iso CANB!, LAE !), Papua New Guinea, Central Province, W of Port Moresby, Brown River Forest Reserve , alt. c. 60 m, 14 June 1960.

Tree to 11 m tall, to 12 cm dbh; bark pale brown to grey, smooth. Vegetative branchlet terete, rounded, 3‒4 mm diam; bark dull, furfuraceous, flaking or peeling. Leaf lamina elliptic or rarely obovate, 7‒12(‒15.5) by 3‒6(‒7) cm, 1.9‒2.8 times as long as wide; base cuneate or obtuse; apex acuminate; acumen flat; margin flat; lamina coriaceous; primary and secondary venation distinctly different with secondaries relatively little developed and not or rarely joining the intramarginal vein; primary veins 20‒30 on each side of the midrib, in median part of lamina at a divergence angle of 60‒70° and 4‒6 mm apart; intramarginal vein present, weakly arched, 1‒2 mm from margin, secondary intramarginal vein absent. Petiole 5‒10 mm long. Reproductive seasonal growth unit with distinct vegetative and reproductive zones. Inflorescence leafless, cauline, fasciculate, up to 9 by 9 cm, major axis 3‒3.5 mm thick at the midpoint, bark furfuraceous; bracts caducous or occasionally a few persistent; bracteoles subtending each flower or subtending lateral flowers of a triad. Flower buds with the apex rounded to obtuse. Flowers with the hypanthium pink and stamens white. Hypanthium dull, smooth, not visibly gland-dotted, minutely but distinctly wrinkled, ribbed; stipitate; goblet-shaped, 5.5‒6 by 4‒4.5 mm, stipe 1.5‒2 mm long. Calyx lobes 4, transversely semi-elliptic, 1‒1.5 mm long. Petals 5 or 6, calyptrate (coherent and falling as a cap). Staminal disc flat ( Fig. 2 : 1.6). Stamens 90‒100, 5‒9 mm long. Style c. 4.5 mm long. Placentation axile-median; placenta a flattened, peltate cushion. Ovules c. 15 per locule, spreading, arranged irregularly. Mature fruit dark pink, verrucose-wrinkled, obovoid and flattened distally, 13‒15 by 7‒8.5 mm excluding the calyx, with the hypanthium rim not ap- preciably expanding in fruit and c. 3 mm diam; seed ellipsoid, c. 5.5 mm across, cotyledons collateral.

Distribution — Papua New Guinea.

Habitat & Ecology — Transitional forest in foothills, poor primary lowland rainforest. Altitude 25‒60 m.

Note — In fruit, the inner pair of sepals is distinctly larger than the outer pair.

Figures

Map 10 Distribution of Syzygium rubroalabastrum Craven & Damas (■), S. thornei T.G.Hartley & L.M.Perry (✚).

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