Phyllanthus chrysanthus Baill.

Verwijs, J. I. M., Bouman, R. W. & Welzen, P. C. van, 2019, A taxonomic revision of Phyllanthus subgenus Macraea (Phyllanthaceae), Blumea 64 (3), pp. 231-252 : 235-236

2. Phyllanthus chrysanthus Baill. — Map 2

Phyllanthus chrysanthus Baill.(1862a) 238;Müll.Arg.(1863) 34;(1866) 393; Guillaumin (1948) 177; Lobr.-Callen et al. (1988) 294; M. Schmid (1991) 48. — Diasperus chrysanthus (Baill.) Kuntze (1891) 598. — Lectotype (designated by Schmid 1991): E. Vieillard 1201, 1855 (P (P00066057); iso P (P00066058)), New Caledonia, Balade.

Phyllanthus persimilis Müll.Arg. (1863) 34; (1866) 392. — Lectotype (designated here): E. Vieillard 1201 p.p., 1855 (G-DC ( G00318228 )), New Caledonia, Balade.

(Prostrate) shrubs, 10‒100 cm high, monoecious; branches (minutely) ridged, brown, older branches subcylindrical, glabrous, younger branches subcylindrical or distally flattened, often winged and shortly puberulous; internodes 0.2‒4 mm long. Stipules triangular, 1‒2 by 0.5‒1 mm, base bilaterally auriculate, margin entire or (extremely) erose, apex attenuate. Leaves: petiole 0.2‒1 mm long, glabrous; blade elliptic or orbicular, 1.5‒30 by 1‒9 mm, 1‒2.5(‒5) times longer than wide, base rounded or obtuse, margin thickened, flat, apex rounded or obtuse, not mucronate; midrib slightly prominent above, prominent underneath, lateral veins 3‒5 on each side, often not or barely visible, flat on both sides. Staminate flowers 1‒3 together, 1.3‒2 mm diam; pedicel 1‒1.5 mm long, glabrous; sepals 6, elliptic, 0.5‒1.2 by 0.2‒0.8 mm, whitish, (pale) green or (pale) yellow, apex acute or obtuse; disc glands 6, circular, 0.2‒0.3 mm diam, flat; stamens 3, 0.5‒0.8 mm long, filaments free, thecae subglobular, c. 0.2 mm long. Pistillate flowers solitary, 2‒3 mm diam; pedicel 1.5‒2.5 mm long, glabrous; sepals 6, elliptic, 1‒1.5 by 0.5‒0.8 mm, whitish, (pale) green or (pale) yellow, apex obtuse or rounded; disc annular, (slightly) lobed, 0.8‒1 mm diam, c. 0.1 mm high; ovary sessile, oblate(-ovoid), 0.6‒1 mm diam, 0.4‒0.8 mm high, glabrous; style absent, stigmas 3, c. 1 mm long, bifid for between 3/4 and 4/5 of the length, reflexed. Fruits subglobular, 2.2‒3 mm diam, with 3 deep and 3 shallow grooves, often bivalved, glabrous, green or red; pedicel 2‒3.5 mm long, glabrous; columella 0.8‒1 mm long. Seeds 1.2‒2 mm high, c. 1 mm wide, minutely verrucate, chestnut-brown, verrucae circular, randomly placed or in (indistinct) longitudinal lines.

Distribution — New Caledonia.

Habitat & Ecology — Occurring in maquis shrubland, forests and near rivers, on rocky, alluvium, laterite and/or serpentine soils. Altitude: 0‒1150 m. Flowering and fruiting all year round.

Note — According to Guillaumin (1948), P. chrysanthus can be distinguished by its randomly positioned verrucae on the seeds and the smooth ovary, while P. virgatus from New Caledonia has seeds with the verrucae in a linear pattern and the ovary can be either smooth or verrucate. However, seeds with randomly positioned verrucae have been found in specimens of P. virgatus from all over Asia and Australia, not just from New Caledonia. A better distinctive character is the thickened leaf margins, in comparison to the flat or revolute leaf margins of P. virgatus , and the more prominent midvein in P. chrysanthus .

Key to the varieties

1. Branches glabrous, flattened, especially distally. Leaf blades (2‒)5‒19(‒30) mm long........... a. var. chrysanthus

1. Young branches distally shortly puberulous or minutely verrucate, subcylindrical, only slightly flattened. Leaf blades 1.5‒10 mm long................................ 2

2. Leaf blades 1.5‒3.5(‒5) by 1‒2 mm. Staminate sepals c. 1.2 mm long. Pistillate sepals c. 1.5 mm long............................................ b. var. deverdensis

Figures

Map 2 Distribution of Phyllanthus chrysanthus Baill. var. chrysanthus (●), P. chrysanthus var. deverdensis M.Schmid (▲) and P. chrysanthus var. micrantheoides (Baill.) M.Schmid (■) on New Caledonia.