Microcos erythrocarpa (Ridl.) Airy Shaw

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 : 280

2. Microcos erythrocarpa (Ridl.) Airy Shaw — Fig. 4 ; Map 2

Microcos erythrocarpa (Ridl.) Airy Shaw (1949) 160; I.M.Turner (1997) 487. — Grewia erythrocarpa Ridl.(1920) 174,p.p. (quoad specim. Ridley 15908); Ridl.(1922) 301, p.p.; Burret (1926) 731 (as an excluded species); Kochummen (1973) 397. — Lectotype (designated here): Ridley 15908 (holo K; iso SING), Peninsular Malaysia, Selangor, Sempang Mines.

Small tree to 8 m tall, dbh to 4 cm; buttresses absent. Twigs smooth, dark brown, densely covered with tufted hairs when young, glabrescent or glabrous when older. Stipules unlobed, lanceolate, 9 –12 by 2 – 2.5 mm, apex acuminate, densely covered with tufted hairs on both sides, caducous. Leaves yellowish green or olive-green on both sides, chartaceous, glabrous or densely covered with simple and tufted hairs on midrib and glabrescent on secondary veins above, glabrous or sparsely covered with simple and tufted hairs on midrib and secondary veins beneath; petioles (7–)8–11(–13) mm long, (1–) 1.3– 2(–2.5) mm thick, yellowish brown to dark brown, apically not swollen, densely covered with tufted hairs; blade narrowly lanceolate to lanceolate or sometimes elliptic, inequilateral, (10–)13– 27(–31) by (3–)4.5–7(– 8) cm, base subcordate or rarely obtuse, margin entire, not ciliate, apex acuminate, acumen 1–2 cm long with a pointed tip; midrib flattened above, raised beneath; secondary veins (5–)8 –10(–13) pairs, slightly conspicuous or inconspicuous above, prominent beneath, basal pair reaching almost or slightly more than 0.25 of blade length, forming an angle of 45° with the midrib; domatia absent; tertiary veins reticulate, inconspicuous above, conspicuous beneath. Inflorescences Type A and Type B panicles, terminal and rarely axillary, (2–)5 –8(–10) cm long, densely covered with tufted hairs; bracts unlobed, lanceolate, (6 –)8 –10(–12) by 2 –2.5(–3) mm, densely covered with tufted hairs on both sides, often persistent; involucral bracts of outer whorl 4 –6.5 mm long, 2 – 3-divided, lobes oblong, 3 –5 mm long, apex acute, smooth outside, densely covered with tufted hairs on both sides, that of inner whorl oblanceolate, 5 –7 by 1–1.8 mm, apex acute, densely or sparsely covered with tufted hairs on both sides. Flower buds globose or narrowly oblong, 2 – 3 by 1.5 – 2 mm, densely covered with tufted hairs; pedicels 0.5 –1.5 mm long, 0.5 – 0.9 mm thick, densely covered with tufted hairs; sepals oblanceolate, 5.5 –7 by 0.8–1.5 mm, densely covered with tufted hairs outside, sparsely covered with tufted hairs inside; petals 5, oblong, 2 –2.3 by 1.4–1.7 mm, apex emarginate or shallowly 2-lobed, outside sparsely covered with tufted hairs at base to c. 0.25 of its length and glabrous towards the apex, inside densely covered with tufted hairs around the glands and glabrous towards the apex, glands globose; androgynophore concave in outline, 1–1.3 mm long, c. 0.5 mm diam, shallowly longitudinally grooved with 5 ridges, glabrous, apical part not expanded outwards, with entire rim covered with tufted hairs or glabrescent; stamens with filaments 2.8–3.5 mm long, glabrous, anthers c. 0.5 mm diam; ovary 3-locular, globose, 1–1.2 mm diam, circular in cross section, densely covered with tufted hairs; style 2.5 – 3 mm long, glabrous. Infructescences densely covered with tufted hairs. Fruits ripening bright red, obovoid, smooth, 2.5 – 3 by 1.5– 2.5 cm, drying brown-black or black, glabrous; apex rounded, without pseudostalk; exocarp membranous and soft; mesocarp 4– 5 mm thick; endocarp thin-coriaceous. Fertile pyrene 1, 1-seeded, 6 – 8 mm long; sterile pyrene inconspicuous.

Distribution — Endemic to Peninsular Malaysia. Found in Perak, Pahang (Fraser’s Hills, Cameron Highlands and Genting Highlands only) and Selangor.

Habitat & Ecology — In mixed dipterocarp and lower montane forests; on ridges and hill slopes, at 900–1400 m altitude. Flowering: March– May, July– September; fruiting: April, July– September, December.

Vernacular name — Damak (Malay).

Notes — Ridley (1920) cited Wray 599 as one of the syntypes of G. erythrocarpa . This collection, however, differs from M. erythrocarpa in the vegetative and reproductive characters, and should be included in M. fibrocarpa .

Similar to M. malayana (a lowland forest species) but can be easily distinguished by its caducous stipules, smaller leaves with shorter acumen, as well as by floral and fruit characters.

Figures

Map 2 Distribution of Microcos erythrocarpa (Ridl.) Airy Shaw ($) and M. riparia (Boerl. & Koord.) Burret (:) in Peninsular Malaysia.

Fig. 4 Microcos erythrocarpa (Ridl.) Airy Shaw. a. Flowering leafy twig; b. detail of abaxial leaf surface near midrib; c. flower buds surrounded by involucral bracts; d. longitudinal section of flower bud; e. flower with sepals and petals removed; f. abaxial surface of petal; g. adaxial surface of petal with gland at base; h. stigma; i. fruiting leafy twig; j. longitudinal section of fruit (a, b, e–h: Kochummen FRI 2980; c, d: Kochummen FRI 16417; i, j: Kochummen FRI 29363). — Drawn by R. Wise, FHO.