Table 3 Camparison of Begonia melanobullata with B. ferox and B. nahangensis
From: Six new species of Begonia (Begoniaceae) from limestone areas in Northern Vietnam
| Â | B. melanobullata | B. ferox(Peng et al.[2013]: figures five and six) | B. nahangensis(Averyanov and Nguyen[2012]: figure seven) |
|---|---|---|---|
Stipule | Â | Â | Â |
 Length | 1.4–2.5 cm | 1–1.7 cm | 0.4–0.6 cm |
Leaf | Â | Â | Â |
 Apex | Acuminate | Acuminate | Obtuse to nearly rounded |
 Shape | Widely ovate to widely elliptic | Ovate | Broadly oblique-ovate or oblique-reniform |
 Conical bullae on upper surface | Present on all leaves; erect hairs tipping bullae persistent | Progressively developed on leaves as the plant matures; hairs on bullae soon deciduous | Unknown |
Inflorescence | Â | Â | Â |
 Peduncle length (cm) | 15–38 | 5–13 | (8–) 10–12 (−14) |
Male flower | Â | Â | Â |
 Tepal color | Greenish | Pale pinkish-yellow | White to light pink |
 Tepal size (mm) | Outer 6–9 × 7–9, inner 5–7 × 3–4 | Outer 9–11 × 6–11, inner 7–11 × 4 | Outer 8–9 in diam., inner 8–9 × 2.5–3.5 |
 Another length (mm) | 0.5–0.8 | Ca. 1 | Ca. 0.5 |
Female flower | Â | Â | Â |
 Tepal color | Yellowish-pinkish | Pinkish-white | Light olive-green |
 Tepal size (mm) | Outer 7–8 × 7–8, inner 4–6 × 2–3 | Outer 8–11 × 7–11 mm, inner 8–9 × 3–4 | Outer (4.5) 5–6 (7) × (8) 9–11 (12) mm, inner 5–6 × 3–3.5 |
Capsule | Â | Â | Â |
 Size | 1.2–1.9 cm long; abaxial wing crescent-shaped, 0.5–0.7 cm wide | 1–1.5 cm long; abaxial wing crescent-shaped, 0.6–0.9 cm wide | 0.8–1 cm long; abaxial wing oblique-triangular, 0.4 cm wide |
Distribution | Northern Vietnam | Guangxi, China | Northern Vietnam |