Syzygium leptopodium Merr. & L.M.Perry

Craven, L. A., 2019, Studies in Papuasian Syzygium (Myrtaceae): 1. Subgenus Perikion revised, Blumea 64 (2), pp. 115-122 : 119-120

6. Syzygium leptopodium Merr. & L.M.Perry — Fig. 1 ; Map 3

Syzygium leptopodium Merr.& L.M.Perry (1942) 284. — Type: Clemens 5326 (holo A n.v.; iso L!), Papua New Guinea, Morobe Province, Ogeramnang , forest, c. 1770–1830 m, 8 Feb. 1937.

Treelet, shrub or tree, usually to 8 m tall (once recorded as being c. 27 m tall), to 8 cm dbh. Vegetative branchlet terete, compressed or quadrangular, rounded or winged (if present, wings are narrow), 0.8–1.5 mm diam; bark dull, bark smooth or cracked (cracking is fine and approaching striate), not or only slightly glandular-verrucose, persistent or peeling in relatively thin strips. Leaf lamina (2–)4–7(–8.5) by (1.2–)1.7–2.4(–4) cm, 2–3.2 times as long as wide, narrowly elliptic, elliptic, narrowly ovate or ovate; base narrowly cuneate, cuneate, obtuse or occasionally rounded; apex long or short acuminate or acute (rarely abruptly acuminate); acumen flat; margin flat or slightly; chartaceous or coriaceous; primary and secondary venation distinctly different with secondaries relatively little developed and not or rarely joining the intramarginal vein; primary veins 6–17 on each side of the mid-rib, in median part of the lamina at a divergence angle of 50–90°, (1–)2–3(–5) mm apart; intramarginal vein present, weakly or strongly arched, (0.3–)0.5–1(–2) mm from margin; secondary intramarginal vein often present at the margin but not strongly developed. Petiole 0.5–4 mm long. Reproductive seasonal growth unit with a reproductive zone only. Inflorescence terminal, distal or median axillary, or lateral below the leaves (ramuline or ramine), 1- or 2- to few-flowered, paniculate or racemose up to 1.2–3.5 by 0.2–3 cm, major axis 0.4–0.6 mm thick at the midpoint; bark glandular-verrucose or smooth; bracts deciduous or caducous; bracteoles sometimes present but apparently not in all flowers, caducous (rarely a few persisting to anthesis). Flowers white, cream or mauve (once described as whitish lilac), calyptrate (petals coherent and falling as a cap). Hypanthium dull, glandular-verrucose, visibly gland-dotted, plane or weakly ribbed; stipitate; elongated goblet-shaped, very elongatedly stipitate-bowl-shaped, or thickly narrowly obconic (occasionally very narrowly obconic); 7.5–14.5 by 2–3 mm wide; stipe 1–3 mm long. Calyx lobes 2 –4, depressedly triangular, very depressedly triangular, oblong or triangular, (0.2–)0.3–0.5(–0.7) mm long. Petals c. 4–7; coherent and caducous, c. 1.5–2.3 mm long. Staminal disc raised ( Fig. 1 : 4.2). Stamens numerous, 1.75–7 mm long. Style 4–7 mm long. Placentation axile-median; placenta more or less flattened, narrowly obovoid. Ovules c. 6–12 per locule, pendulous, arranged in two longitudinal rows (one row on each placental lobe). Mature fruit wine red, orange red, dark or red, magenta, maroon or purplish black, glandular-verrucose, plane or weakly ribbed, subpyriform or ellipsoid, 10–12 by 6–9 mm (excluding the calyx), the hypanthium rim not appreciably expanding in fruit; seed a spheroid or broadly obovoid and deeply impressed at the apex, 5.5–6 mm across; cotyledons interlocked by an intrusive weakly ramifying tissue, collateral or superposed.

Distribution — Indonesia (Papua Barat, Papua); Papua New Guinea.

Habitat & Ecology — Mossy mid-montane forest, montane rainforest with Castanopsis , oak forest, mixed degraded rainforest, forest remnant in river gorge, secondary forest, lower montane rainforest, Nothofagus forest, mossy fagaceous forest, primary forest, edge of Barringtonia - Leptospermum swamp, rocky open situation. Altitude 50–2200 m.

Notes — See under S. claviflorum for notes on differences between that species and S. leptopodium .

The basic floral units within the inflorescence are monads and triads. Sometimes an inflorescence consists of a single monad, or an axis with 2 proximal monads on short axes then 2 sessile monads with a terminal triad or 5-flowered cluster. Often it consists of an axis with 2 sterile monads and the terminal 3- or 5-flowered unit, or it may be a sessile 3- or 5-flowered unit without any peduncle.

Flowers with only 2 calyx lobes were observed in Van Royen 4945.

Figures

Map 3 Distribution of Syzygium kokomo Craven (●) and S. leptopodium Merr. & L.M.Perry (■).

Fig. 1 Diagrams of staminal disc types occurring in Syzygium subg. Perikion species, showing staminal discs that are flat (1.1–1.10), descending (2.5), ascending (3.2) and raised (4.2). Within the flat staminal disc type, structure may differ in the degree of ‘lip’ projection at the inner edge of hypanthium apex (1.4, 1.5, 1.6 and 1.9) and the presence of a grooved petal insertion point (1.10).