Syzygium folidorhachis Merr. & 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 : 67

11. Syzygium folidorhachis Merr. & L.M.Perry — Map 3

Syzygium folidorhachis Merr. & L.M.Perry (1942) 276. — Type: Brass & Versteegh 11917 (holo A n.v.; iso BRI!, LAE !, L n.v.), Indonesia, Papua Province, 15 km SW of Bernhard Camp, Idenburg River , in primary forest on slope of ridge, alt. 1730 m, Jan. 1939.

Tree to 18 m tall, to 54 cm dbh; bark dark brown, scaly. Vegetative branchlet terete or compressed, rounded, 3.5 mm diam; bark glossy, smooth, slightly glandular-verrucose, persistent. Leaf lamina elliptic or broadly elliptic, 13.5‒16 by 8‒9.5 cm, 1.7‒1.8 times as long as wide; base attenuate; apex rounded or roundly acuminate; margin flat; cartilaginous; primary and secondary venation generally similar with all or nearly all secondaries joining the intramarginal vein; or distinctly different with secondaries relatively little developed and not or rarely joining the intramarginal vein; primary veins c. 20 on each side of the midrib, in median part of lamina at a divergence angle of 75‒80° and 6‒10 mm apart; intramarginal vein present, weakly arched, 2‒3 mm from margin; secondary intramarginal vein pre- sent. Petiole 3‒6 mm long. Reproductive seasonal growth unit with a reproductive zone only. Inflorescence leafless, cauline, paniculate, up to 10‒25 by 4‒18 cm, bark furfuraceous. Hypanthium strongly furfuraceous, not stipitate. Placentation axile-median; placenta a subcircular cushion. Ovules 9–11 per locule, spreading, arranged irregularly. Open flowers and fruit not seen.

Distribution — Indonesia (Papua Province).

Habitat & Ecology — Primary rainforest on ridge slope. Altitude 450‒1730 m.

Notes — 1. Hartley & Perry (1973) included S. folidorhachis in S. furfuraceum because they considered the “distinguishing character of prominent reticulate venation may well be the result of variation in habitat”. The re-appraisal of specimens referred to S. furfuraceum by Hartley & Perry in their 1973 publication has resulted in several new species being segregated and the distinctness of S. folidorhachis from S. furfuraceum has become more evident. For example, the leaf lamina in S. folidorhachis is elliptic or broadly elliptic, the base attenuate and there are c. 20 primary veins on each side of the midrib; in S. furfuraceum it is broadly oblong or sometimes obovate, the base is obtuse and there are 30‒37 primary veins on each side of the midrib.

2. The species is known from two collections only.