Syzygium sambogense 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 : 78-79

36. Syzygium sambogense T.G.Hartley & L.M.Perry — Fig. 2 : 1.2; Map 9

Syzygium sambogense T.G.Hartley & L.M.Perry (1973) 207. — Type: Hoogland 3838 (holo A n.v.; iso CANB!, LAE !, BM, BRI, L, all n.v.), Papua New Guinea, Northern (Oro) Province ,along Samboga River near crossing W of Embi Lakes ,stony riverside flooded by high water,alt. c. 60 m, 5 Sept.1953.

Tree to 7 m tall, to 15 cm dbh; outer bark pale grey-brown, inner bark pale brown, smooth. Vegetative branchlet terete, rounded, 3‒5 mm diam; bark dull, bark smooth, not glandular-verrucose, flaking in relatively large pieces or peeling in relatively thin strips. Leaf lamina oblong, elliptic or sometimes obovate, 9.5‒23 by 5‒8.5 cm, 1.8‒2.9 times as long as wide; base cuneate; apex acute to short-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 35‒40 on each side of the midrib, in median part of lamina at a divergence angle of 60‒70° and 4‒8 mm apart; intramarginal vein present, weakly arched, 1‒3 mm from margin, secondary intramarginal vein present. Petiole 5‒15 mm long. Reproductive seasonal growth unit with a reproductive zone only or with distinct vegetative and reproductive zones. Inflorescence leafless or leafy, apparently cauline, paniculate (sometimes elaborately), up to 12 by 13 cm, major axis c. 4 mm thick at the midpoint, bark furfu- raceous; bracts persistent or caducous (persistent especially on the distal axes); bracteoles subtending each flower, cadu- cous. Flower buds with the apex rounded to obtuse. Flowers pale pink. Hypanthium dull, smooth; not visibly gland-dotted, ribbed; not stipitate; obconic, 5‒6 by 3.5‒4 mm. Calyx lobes 4, transversely semi-elliptic, semicircular or obtusely depressedly triangular, c. 1 mm long. Petals 4, calyptrate (coherent and fall- ing as a cap). Staminal disc flat ( Fig. 2 : 1.2). Stamens c. 130, up to 10 mm long. Style c. 6 mm long. Placentation axile-median; placenta a narrowly ellipsoid flattened cushion, apparently not peltate. Ovules c. 12 per locule, spreading to ascending, arranged irregularly. Mature fruit pale red, smooth, ellipsoid, up to 20 by 15 mm excluding the calyx, with the hypanthium rim not appreciably expanding in fruit and c. 4 mm diam; seed ellipsoid, c. 9 mm across, cotyledons collateral.

Distribution — Papua New Guinea.

Habitat & Ecology — Stony riverside flooded by high water, steep sandy river bank. Altitude 50‒60 m.

Notes — 1. The CANB specimens of Hoogland 3838 include an inflorescence in which the main axis apparently aborted with one of the resulting lateral axes being leafy and the other entirely reproductive.

2. The species is known from two collections only.

Figures

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