Phyllanthus aoraiensis Nadeaud

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

1. Phyllanthus aoraiensis Nadeaud — Map 1

Phyllanthus aoraiensis Nadeaud (1873) 73; Drake (1892) 286; (1893) 181; J. Florence (1997) 122; W.L.Wagner & Lorence (2011) 69. — Lectotype (designated by Florence 1997): J. Nadeaud 459 (P (P00636870); iso G, P (P00636871, P00636872)), Tahiti.

Shrubs, 2‒3 m high, monoecious; branches glabrous, strongly winged, wings 0.8‒1 mm wide; internodes 11‒26 mm long. Stipules triangular, scarious, c. 0.8 mm long, caducous, flat, thin, base auriculate, margin entire, apex acute. Leaves: petiole 1‒3 mm long, glabrous; blade ovate-oblong, 45‒125 by 17‒47 mm, 2.2‒3.3 times longer than wide, subcoriaceous, glabrous, base (sub)cordate, weakly asymmetric, margin thickened, apex acute; midrib flat on both sides, lateral veins 9‒11 on each side, flat. Staminate flowers few, axillary, c. 0.7 mm diam; pedicel 10‒20 mm long, glabrous, thicker than pistillate one; sepals 5, red, in two indistinct whorls, ovate, apex obtuse, recurved; disc glands 5; stamens 3, fusion of filaments unknown, thecae rounded. Pistillate flowers solitary, axillary; pedicel> 20 mm long, sepals 5, red, in two indistinct whorls, oblong, 1‒2 mm high, apex acute; disc entire, weakly lobed; ovary sessile, with each locule grooved; style absent, stigmas 3, bifid, recurved. Fruits 4‒5 mm diam, 6-grooved, glabrous; pedicel 12‒30 mm long; columella 1.3‒1.9 mm long. Seeds 4‒5 mm long, verrucate, verrucae not known in detail.

Distribution — Endemic to Tahiti (Aorai mountain).

Habitat & Ecology — Found on mountains at 1 000 m altitude. Flowering and fruiting in November (based on only the type collection).

Note — A species morphologically very close to P. urceolatus and tentatively placed here in subg. Macraea . This species is endemic to Tahiti, but has not been collected since 1857 and is presumed extinct ( Florence 1997, Wagner & Lorence 2011). Phyllanthus aoraiensis is easily distinguished from P. urceolatus and P. pacificus by the very large wings on the branches, the larger seeds and its red flowers. Unfortunately, only the type material was available online, thus descriptions of fruits and flowers have been completed from literature (e.g., Florence 1997).

Figures

Map 1 Distribution of Phyllanthus aoraiensis Nadeaud (●) and P.urceolatus Baill. (▲) in French Polynesia.