Syzygium hartleyi 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 : 69-70

16. Syzygium hartleyi Craven & Damas , sp. nov. — Fig. 2 : 1.4; Map 6

From Syzygium furfuraceum Merr. & L.M.Perry it differs in having a narrowly elliptic,elliptic or sometimes obovate leaf lamina with a cuneate base (broadly oblong or sometimes obovate and obtuse in S. furfuraceum ); a glossy, non-furfuraceous hypanthium (dull and furfuraceous in S. furfuraceum ); and an axile-median placentation with 2‒5 ovules per locule (axile-basal and with 15‒26 ovules per locule in S. furfuraceum ). — Type: Hartley 9630 (holo CANB!; iso A, L, both n.v., LAE !), Papua New Guinea, Morobe Province, c. 11 km N of Lae , near the Butibum River,in primary rainforest, alt. c. 60 m, 24 Dec. 1961.

Etymology. The specific epithet honours Thomas (Tom) Gordon Hartley (1931‒2016), an authority on Indo-Pacific Rutaceae , and who made many stimulating plant collections in New Guinea during a phytochemical survey in the early 1960s (Hartley et al. 1973). Tom worked up his and other col- lections of New Guinean Syzygium with Lily M. Perry at Harvard University and they published a much needed key to the genus ( Hartley & Perry 1973). That research was the stimulus for his continued work in Canberra with Lyn Craven on the group.

Tree to 10 m tall, to 15 cm dbh; outer bark reddish brown, flaky. Vegetative branchlet terete, rounded, 1‒5 mm diam; bark dull, smooth or sometimes furfuraceous, not glandular-verrucose, bark flaking or peeling. Leaf lamina narrowly elliptic, elliptic or sometimes obovate; 8‒13.6 by 2.5‒5.7 cm wide, 2.4‒3 times as long as wide; base cuneate; apex acuminate to long acuminate; acumen flat; margin flat; thinly coriaceous; primary and secondary venation generally similar with all or nearly all secondaries joining the intramarginal vein, primary veins 30‒46 on each side of the midrib, in median part of lamina at a divergence angle of 50‒60° and 2–4 mm apart; intramar- ginal vein present, weakly arched, 0.2‒0.5 mm from margin, secondary intramarginal vein absent. Petiole 5‒8 mm long. Reproductive seasonal growth unit with a reproductive zone only. Inflorescence generally leafless or rarely a leaf within the inflorescence; on branchlets below the leaves or on branches or cauline, paniculate, up to 3.5‒7.5 by 2.5‒4.5 cm, major axis 1.5‒1.7 mm thick at the midpoint, bark furfuraceous; bracts usu- ally persistent; bracteoles subtending each flower, persistent. Flower buds with the apex rounded to obtuse. Flowers cream. Hypanthium glossy, striate-glandular and wrinkled, visibly gland-dotted; stipitate or not; obconic, stipitate-obconic or shortly broadly clavate, 2‒2.5 by 1.7‒2 mm wide, stipe 0‒0.25 mm long. Calyx lobes 5 on a rim of tissue and 0.3‒0.5 mm long including the rim. Petals 5, calyptrate (coherent and falling as a cap). Staminal disc flat ( Fig. 2 : 1.4). Stamens 60‒65, 1.2‒2.8 mm long. Style 2‒2.5 mm long. Placentation axile-median; placenta is a small cushion; ovules 2‒5 per locule, spreading, arranged radially in one row, or arranged irregularly

Map 6 Distribution of Syzygium hartleyi Craven & Damas (●), S. hentyi Craven & Damas (■), S. hooglandii Craven & Damas (▲), S. idanum Craven & Damas (★), S. kosteri Craven & Damas (◆), S. kui Craven & Damas (✚).

(when 4, 2 ovules are collateral on each lobe of the placenta). Mature fruit purple, strongly wrinkled (glands are discernible but are not prominent), depressed-spheroid, c. 8 by 10 mm excluding the calyx, with the hypanthium rim c. 3 mm diam; seed depressed spheroid, c. 7.5 mm across, cotyledons collateral.

Distribution — Papua New Guinea.

Habitat & Ecology — Primary rainforest, rainforest on slope. Altitude 60‒250 m.

Notes — 1. In Hartley 9630, the calyx is a rim of more or less translucent tissue c. 0.2 mm long with 5 protrusions (represent- ing the lobes) each c. 0.3 mm long including the rim. In Robbins 2138, the rim is much less well developed and the calyx lobes are distinct and up to c. 0.5 mm long.

2. Hartley & Perry (1973) tentatively referred specimens of this species to S. iteophyllum Diels but this placement cannot be confirmed. Until type material of S. iteophyllum is located, the correct application of the name cannot be determined.

Figures

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