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Malesian Euphorbiaceae Descriptions |
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Stuppy, W., P.C. van Welzen, P. Klinratana & M.C.T. Posa. 1999. Revision of the genera Aleurites, Reutealis and Vernicia (Euphorbiaceae). Blumea 44: 73–98.
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Vernicia Lour., Fl. Cochinch. (1790) 586; Fl. Cochinch. ed. 2 (1793) 720; Airy Shaw, Kew Bull. 20 (1967) 394; G.L.Webster, Ann. Missouri Bot. Gard. 81 (1994) 114; Stuppy et al., Blumea 44 (1999) 88; Radcl.-Sm., Gen. Euphorbiacearum (2001) 331; Stuppy et al. in Welzen & Chayam., Fl. Thailand 8, 2 (2007) 585; G.L.Webster in Kubitzki, Fam. Gen. Vasc. Pl. 11 (2014) 183. — Aleurites J.R.Forst. & G.Forst. section Dryandra (Thunb.) Müll.Arg. in DC., Prodr. 15, 2 (1866) 723; Pax in Engl., Pflanzenr. IV.147 (1910) 132. — Type: Vernicia montana Lour.
Dryandra Thunb., Fl. Jap. (1784) 13, t. 27, nom. reji. [non R.Br., Trans. Linn. Soc. 10 (1810) 221, nom. conserv., Proteaceae]. — Type: Dryandra cordata Thunb. [= Vernicia cordata (Thunb.) Airy Shaw]
Elaeococca Comm. ex A.Juss., Euphorb. Gen. (1824) 38, nom. superfl.; Blume, Bijdr. (1825) 618. — Type: Elaeococca verrucosa A.Juss [= Vernicia cordata (Thunb.) Airy Shaw]
Shrubs or trees, monoecious or sometimes dioecious, deciduous or evergreen. Bark pale grey, with many tiny brownish lenticels. Indumentum of whitish or fulvous to ferruginous, simple or bifurcate hairs, at least present on young shoots, leaves and petioles, glandular or stinging hairs absent. Young twigs terete, striate, pubescent, dark brown with bright lenticels. Stipules triangular-lanceolate or lanceolate, subglabrous, early caducous, leaving fairly prominent scars. Petiole terete, striate, pubescent when young, with two sessile or stalked glands adaxially at junction with blade. Leaves alternate, simple, ovate to broadly ovate or shallowly to moderately 3- or 5-palmately lobed and then with a conspicuous gland at the nadir of each sinus, tardily glabrescent, upper surface scabrous to (sub)glabrous, lower surface (sub)glabrous except along the major veins and especially in the axils between the midrib and the secondaries; lobes triangular-deltoid; base truncate or shallowly to deeply cordate or reniform; margin entire; apex and lobes obtusely or acutely acuminate to slightly cuspidate; venation basally palmate, 3- or 5-veined from the base, pinnate along the midrib, with 4–6(–8) major lateral veins per side of the midrib, distinct on both sides. Inflorescences terminal, solitary, much-branched corymbiform thyrses, branching from the base, unisexual or bisexual and protogynous with a solitary terminal pistillate flower and several staminate flowers per cymule, axes pubescent when young; bracts inconspicuous, lanceolate, the lower ones sometimes persistent, the upper soon deciduous, marginally or entirely pubescent. Flowers unisexual, showy, slightly zygomorphic, white or reddish white to purple; buds ovoid to ovoid-ellipsoid, apex acuminate to apiculate; calyx closed in bud, later valvately rupturing into 2(3), often unequal lobes, glabrous or pubescent outside, pubescent at the apex inside; petals 5(6), free, imbricate, contorted, obovate, rounded at the apex, with conspicuous parallel veins, clawed, those of the staminate flowers basally adnate to the outermost stamens; disc of 5 or 6(7) free, erect, alternipetalous, glabrous glands. Staminate flowers: pedicel slender, usually longer than in the pistillate flowers, glabrous to pubescent; stamens (7)8–12(–14), in 2 whorls, united into a column, the outer ones free from each other but basally adnate to both the petals and the central staminal column, the inner ones fused for over at least two thirds of their length; the staminal column (sub)glabrous to pilose, the free parts of the filaments glabrous; anthers basifixed to dorsibasifixed, opening introrsely with 2 longitudinal slits, glabrous; pistillode absent. Pistillate flowers: pedicel slender or stout, glabrous to pubescent; ovary superior, 3(–5)-locular, with 1 ovule per locule, sparingly pubescent or densely sericeous; styles ± free or united at the base, bifid, glabrous or basally loosely or densely pubescent. Fruits large, capsular, ovoid to subglobose, tardily dehiscent, glabrous to pubescent. Seeds ecarunculate, obovoid to subglobose, dorsiventrally compressed, pointed or with a minute tip at the micropylar end, brown with longitudinally orientated beige variegations, smooth or conspicuously warty and ridged dorsally and ventrally; hilum large. Embryo straight,embedded in copious endosperm; cotyledons broad, flat.
Distribution — The genus Vernicia comprises 3 closely related species distributed from Burma to Indochina, Thailand, S. China and Japan.
Habitat & Ecology — Vernicia occurs in more temperate latitudes or elevations than Aleurites and Reutealis.
Vernicia montana Lour., Fl. Cochinch. (1790) 587; Fl. Cochinch. ed. 2 (1793) 721; Airy Shaw, Kew Bull. 20 (1967) 394; Stuppy et al., Blumea 44 (1999) 92, Fig. 3; in Welzen & Chayam., Fl. Thailand 8, 2 (2007) 588, Fig. 97. — Dryandra vernicia Corr.Méllo, Ann. Mus. Hist. Nat. 8 (1806) 69, pl. 32, fig. 1, nom. superfl. — Elaeococca vernicia (Corr.Méllo) Spreng., Syst. Veg. 3 (1826) 884, nom. superfl.; Baill., Hist. Pl. 5 (1874) 116 (‘Aleurites verniciflua’). — Elaeococca montana (Lour.) Oken, Allgem. Naturgesch. 3 (1841) 1599. — Aleurites vernicia (Corr.Méllo) Hassk., Flora 25, Beibl. 2 (1842) 40 — Aleurites montana (Lour.) E.H.Wilson, Bull. Imp. Inst. Gr. Brit. 11 (1913) 460; Hemsl., Bull. Misc. Inform. (1914) 3; Merr., Trans. Amer. Philos. Soc. new ser., 24 (1935) 239; Backer & Bakh.f., Fl. Java 1 (1963) 478; E.Walker, Fl. Okinawa S. Ryukyo Isl. (1976) 644. — Type: Loureiro s.n. (BM) Cochinchina.
Aleurites cordata auct. non Steud.: Müll.Arg. in DC., Prodr. 15, 2 (1866) 724; Hemsl., Bull. Misc. Inform. (1906) 120; Gagnep. in M.H. Lecomte, Fl. Indo-Chine 5 (1925) 291; all p.p., only Vernicia montana and synonyms.
Dryandra verrucosa auct. non Royle: Royle, Illr. Bot. Himal. Mts. (1836, 1840) 328, 452, p.p., material.
Shrub or tree, usually monoecious, sometimes dioecious, flat-topped, much branched, evergreen, up to 10–15 m tall. Indumentum ferruginous. Stipules 3–5 by 2–3 mm, (sub)glabrous. Petiole 4.5–15(–23) cm by 1.5–4 mm; glands at the apex clavately stalked, turbinate, tip concave (cup-shaped), red in fresh leaves, exudating a sweet sap, 1.5–5 by 0.5–2 mm. Leaf blade not or very often (esp. on young trees and vigorous shoots) shallowly to moderately 3- or 5-lobed, with a large, subsessile discoid, concave gland at the nadir of each sinus, (6–)10–20(–27) by (4–)10–20(–28) cm, ratio 1–1.4, densely pubescent above, sparingly so beneath, glabrescent, apex and lobes acutely acuminate to slightly cuspidate, without a gland at the top. Inflorescences usually unisexual. Staminate inflorescences many-flowered, much-branched corymbiform thyrses, significantly larger than the pistillate ones, (10–)15–25 by 15–32 cm, pubescent when young; lower bracts often leaf-like, lanceolate, up to 5.5 by 2 cm, upper bracts triangular-lanceolate to linear-lanceolate, 5–20 by 1–3 mm, densely hairy when young. Pistillate inflorescences as the staminate ones, but fewer-flowered and significantly smaller, (3–)5–12 by 4–15 cm. Flowers white, reddish brown in the centre, fragrant; buds 10–18 by 4–7 mm; calyx green at the base, otherwise deep pink to pinkish yellow, lobes 10–15 by 5–8 mm, (sub)glabrous outside, glabrous inside except for a minute tuft at the very apex; petals narrowly obovate-spathulate, rounded at the apex, 15–35 by 6–10(–15) mm, claw 6–8 by 1.5–2 mm, pubescent inside on the claw, those of the staminate flowers showing a tuft of ferruginous hairs around the place where the filament becomes free from the petal and somewhat further down, otherwise glabrous. Staminate flowers 15–30 by 15–35 mm; pedicel 7–12 by 0.6–1 mm; disc-glands subulate or cylindric-fusiform, slenderly triangular in outline, very long and acute, somewhat fleshy, 3–4.5 by 0.3–0.5 mm at the base; stamens (8–)10–12(–14), the 5–9 outer ones shorter than the 3–5(–8) inner stamens, outer filaments 10–16 mm long, inner filaments 12–21 mm long, the free parts of the filaments (sub)glabrous, the staminal column subglabrous to pilose; anthers ovoid, 2–2.5 by 1–1.5 mm. Pistillate flowers 20–25 by 20–30 mm; pedicel rather short, stout, 3–6 by 1.5–2 mm, sparingly pubescent; disc glands shorter and wider as in the staminate flowers, triangular in outline, erect and appressed to the ovary, 1–2 by 0.7–1 mm at the base; ovary oblong-ovoid or ellipsoid and trigonous (tetra- or pentagonous) in cross-section, narrowing into the styles, 3(–5)-locular, 4–5 by 3–4 mm, sericeous; styles bifid, 5–10 mm long, sericeous at the base, glabrous in the distal part. Fruits ovoid to subglobose with rounded-truncate base, apiculate at the apex, surface wrinkled with 3(–5) distinct longitudinal grooves and ridges and a few transverse ribs, 4–6 by 4–4.5 cm, sparingly brown pubescent, especially near the ridges, yellow when ripe. Seeds broadly oboval in dorsal view, pointed at the micropylar end, 20–30 by 20–25 by 11–15 mm, conspicously warty and ridged dorsally and ventrally.
Distribution — Native of S.E. Asia (S. China, Burma, Indochina, Thailand), also widely cultivated in Java and other tropical regions.
Habitat & Ecology — Forest or thicket, disturbed places (e.g. hill dipterocarp forest) and margins of primary evergreen forest, on dry, sandy soil and granite bedrock. Altitude: 0–1200 m.
Uses — The oil is of commercial importance and used in about the same way as the oil from the seeds of V. fordii, i.e. for the manufacture of varnishes, paints, linoleum, etc. (A.C. Smith, 1981).
Vernacular names — English: Chinese Wood Oil. China: Mu-yu (Webster, 1967), Shan t'ung.
