Volume 13 > Part 4 > Year 2017 > Page 665 > Dipterocarpaceae > Vatica

1. Vatica acrocarpa Slootenwfo-0000423141

Bull. Jard. Bot. Buitenzorg III, 17: 241. 1942.; El-Taguri & Latiff, Malaysian Forester 75(2): 127–134. 2012.— Vatica umbonata subsp. acrocarpa (Slooten) P.S.Ashton., Gard. Bull. Sing. 31: 17. 1978; Fl. Males., Ser. 1, Spermat. 9: 349. 1982. Fig. 43. Plate LXVIII: 1–3.

Accepted Name : This is currently accepted.

Synonyms & Citations :

Description : Tree to 20 m tall; resin amber coloured. Indumentum shortly fine brown tufted tomentose on young twigs, buds, stipules, inflorescences and flower buds. Twigs lenticellate. Stipules ovate, 3–5 by 2–3 mm. Leaves elliptic, 7.5–14 by 3–6.5 cm, coriaceous, glabrous; base acute; apex acute; secondary nerves 7–10 on each side; tertiary nerves reticulate-scalariform; midrib flattened above; petioles 0.8–1.5 cm long, glabrescent. Inflorescences 3–8 cm long; branchlets bearing 2–5 flowers; flowers buds lanceolate, 0.3–1 cm long; pedicels 2–2.5 mm long. Calyx lobes subequal, deltoid, acute, 1.5–2 by 1–1.5 mm. Petals oblanceolate, ca 0.8–1.2 by 2–2.5 mm, slightly contorted, dull yellow, tinged pink outside, white inside, strongly fragrant. Stamens typical; filaments ca as long as anthers; anthers ovate-oblong, to 0.5 mm long; connective-appendages short, acute. Ovary broadly conical, ca 1 by 1.3–1.5 mm, shortly tomentose; style glabrous, ca equal to ovary length; stigma typical. Fruiting calyx lobes equally accrescent, thickened, pericarp slightly corky, somewhat deeply furrowed, connate and fused to lower half of the nut; free lobes triangular, 1.5–2 mm long, slightly reflexed; fruit pedicels stout, 3–4 mm long. Nut subglobose, pericarp fine verrucose, brown to red-brown, 3–4 loculicidal marks, 2–2.5 by 2–2.5 cm; style remnant minute.

Thailand : PENINSULAR: Narathiwat (Waeng).

Distribution : Peninsular Malaysia, Borneo.

Ecology : Evergreen forests, on ridges, ca 600 m alt. Flowering: May–August; fruiting: October–December.

Vernacular : Rue so khao (รือเสาะเขา).

Notes: This taxon has been reinstated at species rank, a move which we support here. It is more closely related to Vatica pauciflora than V. umbonata in the fine verrucose pericarp of the nut with loculicidal marks. It is very rare in Thailand; only one tree has been found.