Phyllanthus wheeleri G.L.Webster

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 : 248-249

23. Phyllanthus wheeleri G.L.Webster — Map 7

Phyllanthus wheeleri G.L.Webster (1995) 266; (1997) 215; Chakrab. & N.P.Balakr. (2018) 309. — Type: LC Wheeler 12437 (holo DAV; iso PDA, US), Sri Lanka, Central Province, Dambulla Rock .

Phyllanthus gardnerianus ( Wight) Baill.var. pubescens Thwaites (1861) 282 (‘ gardneri’). — Phyllanthus simplex Retz. var. gardnerianus f. pubescens (Thwaites) Müll.Arg. (1863) 33. — Lectotype: (designated by Webster 1995): Thwaites C.P. 178 (K; iso PDA), Sri Lanka, Galagama.

Small shrubs, monoecious; branches brown, glabrous or hirsute, ridged, distally brown or sage-green, slightly flattened and with 2 larger ridges; internodes 2 ‒5 mm long. Stipules triangular, 1‒1.5 by 0.4 ‒ 0.8 mm, base rounded, margin entire or erose, apex attenuate. Leaves: petiole c. 0.5 mm long, glabrous; blade elliptic or obovate, 5 ‒13.5 by 2 ‒7 mm, 1.8‒ 2.4 times longer than wide, green, base asymmetric, obtuse, margin not thickened, slightly revolute, apex obtuse or rounded, younger leaves usually hirsute on both sides, older leaves often glabrous; midrib flat above, prominent underneath, lateral veins 5 ‒7 per side, slightly prominent on both sides. Staminate flowers solitary or in pairs, c. 1 mm diam; pedicel 2 ‒2.5 mm long, glabrous, slender; sepals 6, elliptic, c. 1 by 0.5 mm, apex obtuse; disc glands 6, circular, c. 0.2 mm diam, flat; stamens 3, c. 0.6 mm long, filaments free, reflexed, thecae ovoid, c. 0.2 mm long. Pistillate flowers solitary or in pairs, c. 1 mm diam; pedicel 2.5 ‒ 4 mm long, glabrous; sepals 6, ovate, c. 1 by 0.2 mm, apex acute; disc glands 6, sometimes sticking out between the sepals, cuneiform or obcordate, 0.2 ‒0.5 by 0.2 ‒0.3 mm, flat; ovary sessile, globular, c. 0.7 mm diam, c. 0.7 mm high, densely hirsute; style absent, stigmas 3, c. 0.5 mm long, bifid for 3/4 of the length, reflexed. Fruits subglobular, 2 ‒ 2.5 mm diam, 6-grooved, hirsute, rarely glabrous; pedicel 3‒ 4 mm long, glabrous; columella c. 1 mm long. Seeds c. 1‒1.2 by 0.8 ‒1 mm, smooth or verrucate, light brown, verrucae circular, in (indistinct) linear lines.

Distribution — Sri Lanka.

Habitat & Ecology — On shady and semi-shady red clay and sandy soils, often on road banks. Altitude: c. 230 m. Flowering and fruiting: October till May, possibly all year round.

Note — This species can be distinguished from other species of subg. Macraea by the segmented pistillate flower disc. There are a few other species with a segmented pistillate disc: Phyllanthus dumosus has smaller orbicular leaves and the ovary is glabrous; P. tenuipes has the ovary on a gynophore and a style; P. ussuriensis has minute disc glands and glabrous, elliptic leaves; and P. womersleyi can be distinguished by its (sub)orbicular leaves, prostrate habit and connate stamens.

Figures

Map 7 Distribution of Phyllanthus gardnerianus (Wight) Baill.(●), P.macraei Müll.Arg. (▲), P. myrtifolius (Moon ex Wight) Müll.Arg. (■) and P. wheeleri G.L.Webster (✚) in S India and Sri Lanka.