Volume 13 > Part 4 > Year 2017 > Page 659 > Dipterocarpaceae > Shorea

24. Shorea siamensis Miq.wfo-0001277244

Ann. Mus. Bot. Lugduno-Batavi 1: 214. 1864; P.S.Ashton, Gard. Bull. Singapore 31: 39. 1978; Smitinand, Santisuk & Phengklai, Thai Forest Bull., Bot. 12: 66. 1980; P.S.Ashton, Fl. Males., Ser. 1, Spermat. 9: 466. 1982; Smitinand, J.E.Vidal & P.H.Hô, Fl. Cambodge, Laos & Vietnam 25: 94, t. 17, figs. 6–10. 1990; Pooma & M.F.Newman, Thai Forest Bull., Bot. 29: 173. 2001; Symington, P.S.Ashton & S.Appanah, Malayan Forest Rec. 16: 119. 2004; Gardner, Sidisunthorn & Chayamarit, Forest Trees S. Thailand Vol. 1: 468, fig. 697. 2015.— Pentacme siamensis (Miq.) Kurz, J. Asiat. Soc. Bengal, Pt. 2, Nat. Hist. 39: 66. 1870; Craib, Fl. Siam. 1: 145. 1925.— Vateria siamensis (Miq.) Burck, Ann. Jard. Bot. Buitenzorg 6: 184. 1887. Fig. 41. Plate LXVII: 1–3.

Accepted Name : This is currently accepted.

Synonyms & Citations :

Description : Deciduous tree, 5–25 m tall; bark deeply fissured. Indumentum shortly fine tufted tomentose and pubescent, sparsely or densely on buds, stipules, twigs, petioles, lower surface of leaves, inflorescences and flower buds, or most parts completely glabrous. Buds ovoid, 0.3–1 cm long. Stipules ovate, 0.7–2 by 0.5–1.5 cm, semi-persistent, auriculate. Leaves broadly ovate to ovate-oblong, 6.5–25 by 5–20 cm, turning reddish orange before falling; base usually cordate; apex broadly acute or obtuse; midrib flattened, slightly sunk or raised above; secondary nerves 12–20 on each side, occasionally bifurcate, arching near the margin; domatia rarely present, pore-like; tertiary nerves loosely to densely scalariform; petioles 1.5–5 cm long. Inflorescences 5–20 cm long, irregularly branched; branchlets to 6 cm long, bearing 2–6 flowers; flower buds ellipsoid, 1–1.5 by 0.5–1 cm; pedicels 2–6 mm long. Calyx lobes ovate, ca 5 by 3 mm, puberulent. Petals broadly elliptic, 1.5–2 by 1–1.5 cm, conduplicate, cream to yellow. Stamens 15, subequal; filaments ca 2 mm long; anthers with 4 pollen sacs, linear-lanceolate, tapering to apex, 5–6 mm long; connective-appendages slender, curved, ca half as long as anthers, glabrous. Ovary conical, glabrous, ca 2 by 2 mm; stylopodium absent; style columnar, to ca 1 cm long; stigma obscurely lobed, shortly ciliate at tip. Fruiting calyx lobes wing-like, broadly saccate at base, thickened, enclosing less than half of the nut, yellowish or reddish when young, glabrous; 3 longer lobes 5–12 by 1–2.5 cm, very narrow towards base; 2 shorter lobes 2–6 by 0.4–0.6 cm; fruit pedicels stout, 3–8 mm long. Nut ovoid, 1.5–2.5 by 1–1.5 cm, glabrous, not smooth; style remnant to 1 cm long.

Thailand : NORTHERN: Chiang Mai, Chiang Rai, Phayao, Lamphun, Lampang, Phrae, Uttaradit, Tak, Sukhothai, Phitsanulok, Kamphaeng Phet, Phichit; NORTH-EASTERN: Phetchabun, Loei, Bueng Kan, Sakon Nakhon, Mukdahan, Khon Kaen; EASTERN: Chaiyaphum, Nakhon Ratchasima, Buri Ram, Si Sa Ket, Ubon Ratchathani; SOUTH-WESTERN: Uthai Thani, Kanchanaburi (type: Teijsman s.n., holotype -L), Prachuap Khiri Khan; CENTRAL: Suphan Buri, Saraburi; SOUTH-EASTERN: Prachin Buri, Chon Buri, Trat; PENINSULAR: Surat Thani, Phangnga, Krabi, Nakhon Si Thammarat, Trang, Satun.

Distribution : Myanmar, Laos, Cambodia, S Vietnam, Peninsular Malaysia (Langkawi, Perlis, Kedah).

Ecology : Deciduous dipterocarp and dipterocarp pine-oak forests, sometimes on cliffs by the seashore and on limestone in evergreen forests, to 1,300 m alt. Flowering: November–April; fruiting: January–April.

Vernacular : Rang (รัง), rang khao (รังขาว), rang daeng (รังแดง); pao (เปา), pao dok daeng (เปาดอกแดง)(Northern); rang hin (รังหิน), rang yuak (รังหยวก)(Northeastern); riang (เรียง), riang-pha-nom (เรียงพนม)(Khmer-Surin).