Syzygium foremanii Craven & Damas, 2021

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 : 67

12. Syzygium foremanii Craven & Damas , sp. nov. — Fig. 2 : 2.3; Map 3

From Syzygium buettnerianum (K.Schum.) Nied. it differs in having stouter vegetative branchlets (4‒6 mm diam as against 1.1‒2.8 mm in S. buettnerianum ); the leaf lamina broadly elliptic to obovate (in S. buettnerianum the lamina is elliptic, ovate, narrowly elliptic or narrowly ovate); 5 calyx lobes (in S. buettnerianum the calyx is an undifferentiated rim of tissue on which 4 lobes rarely may be evident);the staminal disc ascending (flat in S. buettnerianum ); and c. 55 stamens (as against 30‒35 in S. buettnerianum ). — Type: LAE (Foreman) 52297 (holo CANB!; iso LAE !; BRI, L, both n.v.), Papua New Guinea, Morobe Province, Lae Subprovince , in Eucalyptopsis - Anisoptera forest on low ridge, near Buso village, alt. c. 150 m, 6 Jan. 1973.

Etymology. This species is named in honour of Donald Bruce Foreman (1945‒2004). Don collected extensively in Papua New Guinea when on the staff of the herbarium in Lae between 1969 and 1975.

Tree to 30 m tall, to 50 cm dbh; outer bark greyish to white, papery; inner bark reddish brown. Vegetative branchlet terete, rounded, 4‒6 mm diam; bark dull, smooth, not glandular-verrucose, persistent. Leaf lamina broadly elliptic to obovate, 5.5‒16.7 by 3.5‒8.5 cm, 1.6‒2.2 times as long as wide; base cuneate; apex acuminate; acumen recurved; margin revolute; lamina coriaceous or cartilaginous; primary and secondary venation distinctly different with secondaries relatively little developed and not or rarely joining the intramarginal vein; primary veins 25‒33 on each side of the midrib; in median part of lamina at a divergence angle of 60‒70° and 3‒7 mm apart; intramarginal vein present, weakly arched, 2.5‒3 mm from margin, secondary intramarginal vein present. Petiole 5‒10 mm long. Reproductive seasonal growth unit with distinct vegetative and reproductive zones. Inflorescence leafless, terminal, corymbose, up to 8 by 13 cm, major axis 3‒5 mm thick at the midpoint, bark furfuraceous; bracts persistent; bracteoles subtending each flower, persistent. Flower buds with the apex rounded to obtuse. Flowers pink. Hypanthium glossy to dull, striate-glandular, visibly gland-dotted; stipitate; goblet-shaped to elongated goblet-shaped, 6‒7 by 2.6‒3 mm, stipe 3‒3.5 mm long. Calyx lobes 5, transversely oblong or transversely narrowly semi-elliptic, 0.4‒0.5 mm long. Petals 5, calyptrate (coherent and falling as a cap). Staminal disc ascending ( Fig. 2 : 3.1). Stamens c. 55, 2.5‒7 mm long. Style 4‒4.5 mm long. Placentation axile-median; placenta a hemispherical cushion, slightly peltate. Ovules c. 10 per locule, spreading, arranged irregularly. Fruit weakly glandular-verrucose, more or less smooth, subspheroid, c. 15 by 18 mm excluding the calyx, with the hypanthium rim not appreciably expanding in fruit and c. 3 mm diam; seed depressed spheroid, c. 12 mm across, cotyledons collateral.

Distribution — Papua New Guinea.

Habitat & Ecology — Depleted primary forest, lowland pri- mary rainforest, Eucalyptopsis - Anisoptera forest on low ridge. Altitude 50‒ 200 m.

Note — The species is closely related to S. buettnerianum and may represent an adaptation to ultrabasic soils, which are known to occur in the Buso area. The fruit available for study is not fully mature and consequently the data given above for fruit and seed may require amendment once fully developed fruit become available.

Figures

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