海南山柑 hai nan shan gan

Shrubs, erect or scandent, 2-3 m tall. Twigs terete, smooth, glabrous, base with subulate cataphylls. Stipular spines ca. 2 mm, slightly recurved, apex tan-colored. Petiole 5-12 mm, glabrous; leaf blade oblong-elliptic to elliptic, 6-9(-12) × 2.5-5(-8.3) cm, leathery, yellow and thin when dry, both surfaces glabrous, abaxially with papillae, midvein adaxially flat or slightly sunken, secondary veins 5-8(-10) on each side of midvein and abaxially thick and raised, reticulate veins dense and impressed on both surfaces, base cuneate, almost rounded, or sometimes slightly cordate, apex obtuse and often shortly mucronate. Flowers axillary, solitary or paired, forming a vertical row in apical axils, often with 1 or 2 bunches of subulate small spines between pedicel and petiole which in fruit become woody and 3-5 mm in diam. Pedicel 1-3 cm. Sepals oblong-elliptic, 1.2-2 × 0.5-0.6 cm, ± equal, apex acute; sepals of outer whorl glabrous; sepals of inner whorl shortly tomentose-pannose, margin white and thin. Petals white to sometimes purple, obovate-oblong, 2-3 × ca. 1.5 cm, glabrous. Stamens (50-)60-75; filaments (2.5-)3-4 cm; anthers ca. 2 mm. Gynophore 3-4 cm, glabrous; ovary ovoid, 5-7 mm; placentae 4; ovules many. Fruit yellow to orangish red, ellipsoid to oblong, ca. 5 × 2.5-3 cm, smooth, apex beakless; fruiting gynophore 3-5 mm in diam., woody. Seeds numerous per fruit, dark red when dry, 6-8 × 4-6 × 3-5 mm, smooth. Fl. Jul-Dec, fr. Dec-Mar.

● Forests, open shrubby areas, coastal thickets, open woods; near sea level to 600 m. Hainan.