Microcos lanceolata (Miq.) Burret

Chung, R. C. K. & Soepadmo, E., 2011, Taxonomic revision of the genus Microcos (Malvaceae-Grewioideae) in Peninsular Malaysia and Singapore, Blumea 56 (3), pp. 273-299 : 286-288

6. Microcos lanceolata (Miq.) Burret — Fig. 8 ; Map 6

Microcos lanceolata (Miq.) Burret (1926) 778;I.M.Turner(1997)487.— Inodaphnis lanceolata Miq. (1861) 357; (1867) 89. — Grewia miqueliana Kurz (1872) 398; King (1891) 115; Ridl. (1922) 302; Kochummen (1973) 397; (1997) 429; Whitmore & Tantra (1986) 240. — Type: Teijsmann s.n. (n.v.), W Sumatra, Pajakumbuh.

Small tree to 15 m tall, dbh to 15 cm; buttresses absent. Outer bark smooth, lenticellate, dark brown with grey patches; inner bark red; sapwood white or pale with net-like rays. Twigs smooth, brown to dark brown, covered with minute stellate hairs when young, glabrous when older. Stipules unlobed, lanceolate, 4 – 6(–9) by 0.9 –1.2(–1.5) mm, apex obtuse, sparsely covered with minute stellate hairs on both sides, caducous. Leaves brown to dark brown on both sides, chartaceous or subcoriaceous, glabrescent or glabrous on both sides; petioles 4 –7(–9) mm long, 1–2 mm thick, brown to dark brown, apically not swollen, sparsely covered with minute stellate hairs or glabrous; blade narrowly elliptic to elliptic, equilateral or sometimes inequilateral towards base, (6.5–)7–18(–20) by (2.5 –)3– 5.5(– 6) cm, base narrowly cuneate to cuneate or sometimes shortly attenuate, margin entire, not ciliate, apex acuminate, acumen 0.5–1(–1.5) cm long, blunt; midrib and secondary veins raised on both sides; secondary veins (6 –)7– 8 pairs, basal pair reaching almost 0.25 or occasionally between 0.25 and 0.5 of blade length, forming an angle of less than 45° with the midrib; domatia absent; tertiary veins reticulate, obscure above, conspicuous or obscure beneath. Inflorescences Type A and sometimes Type B panicles, terminal or axillary, 2 – 4 cm long, covered with minute stellate hairs; bracts early caducous; involucral bracts of outer whorl 4 –5 mm long, 2-cleft, lobes ovate, 1.5– 2.3 mm long, apex acute, smooth, blackish, and covered with minute stellate hairs or glabrescent outside, densely covered with stellate hairs inside, that of inner whorl oblanceolate or obovate, 4 – 5.2 by 1.5 –2.2 mm, apex acute or obtuse, covered with minute stellate hairs on both sides. Flower buds obovoid, 3.9 –4.2 by 1.7–1.9 mm, densely covered with stellate hairs; pedicels 0.5 –1.5 mm long, 0.6 – 0.8 mm thick, densely covered with stellate hairs; sepals oblanceolate, 5– 6 by 1–1.5 mm, densely covered with stellate hairs on both sides; petals 5, linear or oblanceolate, 1.5– 2 by 0.2 – 0.5 mm, apex acute, sparsely covered with stellate hairs (outside) or densely covered with stellate hairs (inside) at base to c. 0.25 of its length and glabrous towards the apex on both sides; glands absent; androgynophore cylindrical in outline, 0.2 – 0.3 mm long, 0.8 –1 mm diam, longitudinally grooved, glabrous, apical part slightly expanded outwards, with slightly undulate rim covered with

4 cm

stellate hairs; stamens with filaments 3–4 mm long, glabrous, anthers 0.2 – 0.3 mm diam; ovary 2-locular, globose or ovoid, 0.8–1 mm diam, transversely elliptic with 3 shallow ridges in cross section, densely covered with stellate hairs; style 3.5– 4 mm long, glabrous. Infructescences sparsely covered with minute stellate hairs. Fruits obovoid, smooth, 1.5 –2.5 by 1–1.5 cm, drying chestnut-brown to dull brown, glabrous; apex rounded, without pseudostalk; exocarp brittle; mesocarp 1–3 mm thick; endocarp 0.5–1.5 mm thick, woody. Pyrenes 2, partly connate or free; fertile pyrene 1, 1-seeded, 7–9 mm long; sterile pyrene 1, conspicuous; pyrenes arranged horizontally, with the fertile one nearly of the same size as the sterile pyrene.

Distribution — Sumatra and Peninsular Malaysia.

Habitat & Ecology — In mixed dipterocarp forest; frequently found along rivers or on ridge tops, to 600 m altitude. Flowering: March – June, August– October, December; fruiting: February– April, June– November.

Vernacular names — Batang libut, chenderai hutan, chenderai paya, malabu (Malay).

Uses — Ripe fruits edible (Zainuddin FRI 17941).

1 cm 1 mm

Figures

Map 6 Distribution of Microcos lanceolata (Miq.) Burret in Peninsular Malaysia.

Fig. 8 Microcos lanceolata (Miq.) Burret. a. Flowering leafy twig; b. flower buds surrounded by involucral bracts; c. longitudinal section of flower bud; d. flower with sepals and petals removed; e. abaxial surface of petal; f. adaxial surface of petal without gland at base; g. stigma; h. fruit; i. longitudinal section of fruit; j. cross section of fruit (a –c: Mohzan KEP 99575; d–g: Chelliah KEP 104621; h–j: Chan FRI 16922). — Drawn by M. Nizam, UKMB (a, b, e, f) and by J. Pao, SAR (c, d, g–j).