Phyllanthus myrtifolius (Moon ex Wight) Müll.Arg.

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 : 242-243

13. Phyllanthus myrtifolius (Moon ex Wight) Müll.Arg. — Map 7

Phyllanthus myrtifolius (Moon ex Wight) Müll.Arg. (1863) 35; (1866) 396; Thwaites (1861) 283; Hook.f. (1887) 296; R. Ansari & Jeeja (1993) 141; J. Florence (1997) 134;G.L.Webster (1997) 211; Chantar.(2005) 19;(2007) 493;N.P.Balakr.& Chakrab.(2007) 379;Chakrab.& N.P.Balakr.(2018) 304. — [ Phyllanthus myrtifolius Moon (1824) 65, nom nud.; Baill. (1858) 628 (see note 2).] — Macraea myrtifolia Moon ex Wight (1852) 27, pl. 1902-2; Baill. (1858) 628. — Diasperus myrtifolius (Moon ex Wight) Kuntze (1891) 600. — Lectotype (designated by Webster 1997): G. Gardner s.n. in GHK Thwaites C.P. 650 (K; iso G, PDA), Sri Lanka, Mawelly ganga.

Shrubs, 30‒200 cm high, monoecious; branches brown, glabrous, with ridged and fissured bark, distally scabrid and with 2 minute ridges; internodes 2‒7 mm long. Stipules ovate, 1‒2 by 0.8‒1 mm, base very narrow, hastate, margin entire, apex acute. Leaves: petiole c. 1 mm long, glabrous; blade obovate, 5‒25 by 1‒10 mm, to 2.5‒5.5 times longer than wide, glabrous, upper surface dark green, light green underneath, base very narrow, cordate-sagittate, margin not thickened, (slightly) revolute, apex obtuse or acute; midrib flat above, prominent underneath, lateral veins 4‒8 per side, flat above, prominent underneath. Staminate flowers solitary to 5 together, c. 2.5 mm diam; pedicel 5‒10 mm long, glabrous, slender; sepals 6, apex obtuse, green or (pinkish) red, often with white margins, in two whorls, outer ones ovate, c. 1.5 by 1 mm, inner ones elliptic, c. 1.5 by 0.5 mm; disc glands 6, ovoid, c. 0.3 by 0.2 mm, c. 0.1 mm high, foveolate; stamens 3, c. 0.5 mm long, filaments free, reflexed, thecae ovoid, 0.2‒0.3 mm long. Pistillate flowers solitary or in pairs, 2‒3 mm diam; pedicel 6‒10 mm long, glabrous, slender; sepals 6, apex obtuse, green or (pinkish) red, often with white margins, in two whorls, outer ones ovate, c. 1.5 by 1 mm, inner ones elliptic, c. 1.5 by 0.5 mm; disc hexagonal with the angles alternating with sepals, flat, c. 1 mm diam; ovary sessile, globular, c. 0.5 mm diam, c. 0.5 mm high, glabrous; style absent, stigmas 3, c. 0.5 mm long, bifid for 1/2 of the length, reflexed. Fruits subglobular, c. 3 mm diam, 3-grooved, splitting in three blunt tipped valves, glabrous; pedicel 8‒10 mm long, glabrous; columella not seen. Seeds c. 1.8 by 1.2 mm, smooth or minutely verrucate, chestnut-brown, verruculae rhomboid and stretched widthwise or circular and very small, placed in (indistinct) longitudinal lines.

Distribution — Endemic to Central and South Sri Lanka and cultivated in China, India, Thailand, Singapore, Taiwan, and French Polynesia.

Habitat & Ecology — Common near or even in rivers and on river banks. On granite bedrock and soils with a high water table. Altitude: usually low, up to 900 m. Flowering and fruiting all year round.

Uses — As an ornamental shrub of hedge, as a medicine for genitourinary infections ( Quattrocchi 2016).

Vernacular names — Sri Lanka: Mousetail Plant, Myrtleleaved leaf-flower (Flowers of India, www.flowersofindia.net), China: Liu xian ye xia zhu ( Quattrocchi 2016).

Notes — 1. Similar to P. samarensis , but distinguishable by its glabrous branches, slightly narrower leaves and very narrow cordate-sagittate leaf base.

2. Baillon (1858) treats Macraea myrtifolia as part of Phyllanthus , but does not make the combination, therefore, according to Art. 35.2 ICN ( Turland et al. 2018) the combination Phyllanthus myrtifolius cannot be attributed to him.

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.