Corresponding author: Hironori Toyama (
Academic editor: Pam Soltis
A new species of
Toyama H, Tagane S, Dang VS, Tran H, Nagamasu H, Naiki A, Yahara T (2016) A new species of
From 2013 to 2014, as part of a collaborative programme to document the biodiversity and ecology of Southeast Asia,
Location of Hon Ba Nature Reserve in Vietnam.
This species is similar to
VIETNAM. Khanh Hoa Province, Hon Ba Nature Reserve, evergreen forest margin along streamside, 401 m alt.,
Trees 8–10 m tall. Branches yellow-green when young, turning brown when mature; indumentum sparsely to densely brown stellate hairy when young (denser on the uppermost branch), glabrescent; lenticels more distinct on young branches when dry. Terminal buds naked, narrowly ovoid, ca. 5 mm long, ca. 2 mm wide, having 2 opposite stipules incompletely covering young leaves, linear, ca. 4.5 mm long, ca. 0.5 mm wide, brown stellate hairy. Axillary buds scaled, narrowly ovoid, ca. 3.5 mm long, ca. 1.2 mm wide; bud scales 2, opposite, incompletely covering young leaves, narrowly ovate-oblong, 3–4 mm long, 0.5–1 mm wide, densely brown stellate hairy. Leaf blades elliptic to oblong, 6.5–21.5 cm long, 2.2–8.5 cm wide, coriaceous, lustrous and glabrous on both surfaces except veins below, base obtuse to cuneate, apex acuminate to rounded, margin entire; midribs sunken and glabrous above, prominent and sparsely brown stellate hairy below; secondary veins 5–9 pairs, slightly sunken and glabrous above, prominent and sparsely brown stellate hairy below; tertiary veins reticulate, slightly sunken and glabrous above, prominent and sparsely brown stellate hairy below; petiole 9–14 mm long, sparsely brown stellate hairy; stipules 2, opposite, caducous, linear, 5–8 mm long, 0.5–1 mm wide, brown stellate hairy. Flowers not seen. Infructescences terminal and axillary, racemose, 5–10.3 cm long; peduncles 1.2–4.5 cm long, brown stellate hairy, with 0–2 basal leaves; basal bracts not seen; bracts and bracteoles caducous, narrowly ovate, 1.8–3 mm long, 0.5–1 mm wide (but see note), densely brown stellate hairy; fruiting pedicels 5–8 mm long, densely brown stellate hairy. Floral cups in young fruits, turbinate, 2–3 mm in diameter, densely brown stellate hairy; ovary 2-locular; ovules 1 per locule. Capsules ovoid-globular, 12–16 mm long, 9–10 mm in diameter, woody, dehiscing loculicidally by two 2-lobed valves, sparsely lenticellate, sparsely brown stellate hairy, the length above tepal scar 6.5–9 mm; endocarp loose from woody exocarp. Seeds 2 per capsule, narrowly ovoid, ca. 10 mm long, ca. 4.5 mm wide, ca. 3 mm thick, brownish black, smooth, hilum ca. 4 mm long, ca. 3 mm wide for bigger side (the basal side on the placenta).
VIETNAM. Khanh Hoa Province, Hon Ba Nature Reserve, evergreen forest margin along streamside, 393 m alt.,
This species is only known from Hon Ba Nature Reserve of southern Vietnam. We found only three individuals in the evergreen forest along a stream at ca. 400 m alt. The flora of this area is reported in
Flowering season is unknown. Immature fruits and capsules were observed in July and November.
Critically Endangered
axillary bud bud scale petiole stipule uppermost branch
Terminal and axillary bud of axillary bud apical meristem axillary shoot bud scale branch leaf petiole stipule terminal shoot
The description of bracts and bracteoles is insufficient because most of the bracts and bracteoles had been shed.
The
1 | Leaf lamina brown tomentose with stellate hairs on abaxial surface |
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– | Leaf lamina glabrescent except along veins on abaxial surface |
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2 | Capsules densely lenticellate |
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– | Capsules smooth or sparsely lenticellate |
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3 | Leaves oblong-lanceolate, margin sometimes dentate towards the apex; infructescences 3–5 cm long, capsule glabrous |
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– | Leaves elliptic to oblong, margin entire, infructescences 5–10.3 cm long, capsule sparsely brown stellate hairy |
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We thank staff of the Hon Ba Nature Reserve in Vietnam for their kind supports of field works in the protected area. We thank staff of the following herbaria: