e-Flora of Thailand

Volume 16 > Part 1 > Year 2022 > Page 17 > Annonaceae > Alphonsea

7. Alphonsea isthmicola I.M.Turner & Utteridgewfo-1000001306

Thai Forest Bull., Bot. 45(1): 42. 2017.


Accepted Name : This is currently accepted.


Description : Tree 10–24 m tall; bark dark grey or dark brown, longitudinally striate. Twigs sparsely covered with brown or greyish brown appressed hairs or glabrous when young, later glabrous. Leaves chartaceous or subcoriaceous, elliptic or lanceolate-elliptic, 3.5–9 by 1.5–3.5 cm, base cuneate, apex acute or acuminate, the acumen 2–10 mm long, margins revolute, glabrous or sometimes with long appressed greyish brown hairs on midrib above, glabrous or with sparse brown hairs only on midrib below, midrib plane above, secondary veins 10–12 per side, tertiary venation on lower surface forming a close network; petioles 2–5 mm long. Inflorescences 1–4-flowered, peduncle 1.5–3 mm long, pedicels 3–10 mm long, each bearing a single bract near the base; buds conical. Sepals connate to midpoint, ovate, 1–1.5 mm long, acute or obtuse. Outer petals whitish yellow or yellow, ovate or triangular-ovate, 8–12 by 4–5.5 mm, apex acute, grey-hairy on both sides. Inner petals whitish yellow, lanceolate-ovate to triangular-ovate, 8.5–13 by 3–6 mm, apex obtuse to acute, densely grey-hairy outside, glabrous or sparsely hairy inside. Stamens 20–30, oblong to elliptic, 0.6–1 mm long. Carpels (2–)3–5, ovaries oblong, 1.5–2 mm long. Fruit of 2–5 monocarps borne on a pedicel 8–15 mm long. Monocarps ellipsoid to ovoid, 2.7–5 by 2–3 cm, smooth, densely brown-hairy, apex rounded, base contracted into a stipe 7–10 mm long. Seeds 3–6 per monocarp, ellipsoid, 10–15 by 8–15 mm.


Thailand : PENINSULAR: Surat Thani (Khirirat Nikhom, Ban Na San), Nakhon Si Thammarat (Tha Sala – type: Gardner ST2393, holotype -BKF, isotype -K), Songkhla (Sadao, Rattaphum).


Distribution : Peninsular Malaysia.


Ecology : Lowland evergreen forests on limestone outcrops, 70–270 m alt. Flowering: January–April; fruiting: March, May–August.


Vernacular : Sang yu (สังยู้).


Notes: Material from Songkhla province (Leeratiwong 18-1508) has the leaf and monocarp characters of Alphonsea isthmicola but has longer petals and only two carpels.


Main
SN number Collectors and numbers Provinces
196098 Gardner, S.  ST2393 Nakhon Si Thammarat