Syzygium nomoa Guillaumin

Tuiwawa, S. H., Craven, L. A., Sam, C. & Crisp, M. D., 2013, The genus Syzygium (Myrtaceae) in Vanuatu, Blumea 58 (1), pp. 53-67 : 62-63

13. Syzygium nomoa Guillaumin

Syzygium nomoa Guillaumin (1931) 258. — Typus: Kajewski 128 (lectotype P!, here designated; iso BRI!, K!), Vanuatu, Tanna, Tafea, Lenakel , rainforest, 200 m, 7 Mar. 1928.

Tree up to 25 m tall. Vegetative branchlets quadrangular without wings, c. 6 mm diam; bark dull, smooth, not glandular-verrucose, persistent. Leaf lamina up to 15.6 by 5.8 cm, obovate; base symmetric, attenuate or cuneate; apex retuse or rounded; margin flat; coriaceous; drying greenish brown above; primary vein (midrib) c. 2 mm wide; secondary veins closed, more than 20 each side of primary vein, c. 2 mm apart; intramarginal vein strongly arched, c. 2 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, sparse. Petiole c. 15 mm long; adaxially strongly grooved. Inflorescence terminal, cymose panicle, 5.5–10 by 4–14 cm, 1–2 flowers per anthopodium; hypopodium c. 10 mm long; main inflorescence axis c. 5 mm wide, quadrangular, dull, smooth; bracts deciduous, c. 2 mm long. Hypanthium not stipitate, obconic, c. 8 by 4 mm, dull, not visibly gland dotted; striate. Sepals 4, c. 1 by 3 mm, semicircular, persistent, free. Petals not seen. Stamens many, more than 50, outermost stamens c. 1 cm long; filament free, colour not seen; anther sacs elliptic. Style c. 4 mm long. Fruit black when ripe, smooth, furfuraceous, botuliform to ellipsoid, up to 2 by 1.2 cm.

Distribution & Ecology — Vanuatu (Sanma province: Espiritu Santo; Shefa province: Efate; Tafea province: Aneityum, Erromango, Tanna; Torba Province: Banks islands-Vanua Lava). Syzygium nomoa is endemic to Vanuatu where it is quite common in kauri forest and primary rainforest up to 800 m asl.

Vernacular names — Incaemohos or incaemu (Aneityum).

Uses — A useful timber for building canoes, and for house posts.

Notes — 1. Flowers have been recorded from March to June and fruits from November to March.

2. Syzygium nomoa can be misidentified as S. myriadenum because of the similarities in vegetative features. However, these two species are distinct in leaf size and apex, hypanthium shape and size. In S. nomoa , the leaf lamina is up to 15.6 by 5.8 cm, the leaf apex is round and the hypanthium is obconic, and c. 8 by 4 mm. For S. myriadenum , the leaves are up to 23.5 by 7.2 cm, the leaf apex is acute and the hypanthium is narrowly oblong and c. 17 by 5 mm.

3. Syzygium nomoa has a similar inflorescence branching pattern to S. myriadenum and S. nidie . However, these species are distinct in leaf apex and size. In S. nomoa the leaf apex is round and the leaves are up to 15.6 by 5.8 cm whereas in the latter two species the leaf is acute and up to 23.5 by 7.2 cm and conspicuously acuminate and up to 6.5 by 3.1 cm, respectively.