Syzygium insulare T.G.Hartley & L.M.Perry

Tuiwawa, S. H., Craven, L. A., Sam, C. & Crisp, M. D., 2013, The genus Syzygium (Myrtaceae) in Vanuatu, Blumea 58 (1), pp. 53-67 : 60

7. Syzygium insulare T.G.Hartley & L.M.Perry

Syzygium insulare T.G.Hartley & L.M.Perry (1973) 183. — Typus: Floyd NGF 3546 (holo A n.v.; iso CANB), Papua New Guinea, New Britain, West Nakanai, Galilo village , near Cape Hoskins , 3 Aug. 1954.

Tree or shrub up to 3 m tall. Vegetative branchlets terete to terminally compressed, c. 3 mm diam; bark dull, smooth, not glandular or verrucose, persistent. Leaf lamina c. 26 by 10 cm, broadly ovate; base symmetric, cuneate or retuse; apex acuminate, acumen flat; margin undulate; chartaceous; drying greenish above; primary vein (midrib) c. 1 mm wide; secondary veins open, c. 13 each side of primary vein, c. 24 mm apart; intramarginal vein strongly arched, 2–9 mm from the margin at the lamina midpoint; secondary intramarginal vein weakly arched; tertiary intramarginal vein absent; oil dots present, not visible to the unaided eye in transmitted light, small, moderately dense. Petiole c. 10 by 2 mm, adaxially strongly grooved. Inflorescence terminal, simple dichasia, c. 5 by 4 cm, 3 flowers per anthopodium; hypopodium 8–10 mm long; main inflorescence axis absent; bracts persisting, c. 1 mm long. Hypanthium stipitate, stipe 1–1.4 cm long; campanulate; c. 4 by 3 cm, dull, not visibly gland dotted, ribbed to generally smooth. Sepals 4, c. 5 by 13 mm, subcircular, persistent, free. Petals c. 4, present at anthesis, coherent, semicircular, c. 10 by 20 mm, white; not visibly gland dotted, margin entire. Stamens many, more than 50, outermost stamens c. 25 mm long; filament free, white; anther sacs narrowly oblong. Style c. 25 mm long. Fruit whitish green becoming red when ripe, smooth, plane, fusiform or napiform, up to 16 by 7.5 cm.

Distribution & Ecology — Vanuatu (Malampa province: Malakula; Penama province: Pentecost; Shefa province: Efate; Torba province: Banks Islands-Vanua Lava; Torres Islands, Tegua). In Vanuatu, S. insulare is restricted to the northern islands where it occurs frequently along the coastal zone, although it may occur inland up to 140 m asl. Syzygium insulare also occurs in Papua New Guinea and on the Solomon Islands.

Vernacular name — Nepkrera (Malakula).

Uses — The species is not used by local people.

Notes — 1. It has been recorded to flower between August and September and fruit between October and March.

2. Syzygium insulare occurs in the Bismarck Archipelago, Solomon Islands and Vanuatu. This distribution pattern, i.e. Papuasia-Vanuatu, occurs in several other Vanuatu species.

3. Past collections of this species in Vanuatu (with no specific locality) were mistakenly identified as S. nutans (K.Schum.) Merr. & L.M.Perry. In S. insulare the inflorescence axis is erect whereas in S. nutans , it is pendulous. The anthers of S. insulare are c. 1 mm long thus they are conspicuously large and distinctive relative to the other Syzygium species in Vanuatu. Its inflorescence is very short and unbranched, and at most the flowers are in clusters of three.

4. The vegetative features of S. insulare can be confused with S. richii , however, they are quite distinct in vegetative branchlets, hypanthium and fruit size. In S. insulare , the vegetative branchlets are terete, the hypanthium is up to 4 by 3 cm and the fruit is up to 16 by 7.5 cm. For S. richii , the vegetative branchlets are winged, the hypanthium is up to 2 by 2.5 cm and the fruit up to 3 by 2.1 cm.