Stems clustered, forming small clumps, to 0.9 m tall, 1 cm diameter, green with reddishbrown scales. Leaves 5; sheaths open, not forming crownshafts, 7–13 cm long, covered with reddish-brown scales; ocreas 1–2.5 cm long, early deciduous; petioles 59–78 cm long, green; rachis 38–39 cm long; pinnae 5–7 per side of rachis, linear, contracted at the bases, middle pinna 32–33 cm long, 2 cm wide at the middle, apical pinna 15.5–21 cm long, 2 cm wide at the middle, lobed; veins scarcely raised adaxially. Inflorescences interfoliar, pushing through the persistent, disintegrating, subtending leaf sheaths, erect; peduncles 0.5–0.8 cm long, 0.3 cm wide; prophylls 3–4.5 cm long; rachis absent; rachillae 1–3, 4–4.5 cm long, rectangular in cross-section, glabrous; triads distichously arranged; staminate flowers 6.5 mm long; sepals forming a 3-lobed, flat, membranous calyx 1.5 mm long; petals 3, 6 mm long, triangular, fleshy, acute; stamens 9–13; pistillate flowers 2.5 mm long; calyx 2.5 mm long with 3, free, imbricate, ciliate, nonacuminate sepals; corolla similar to the calyx; ovary 2.5 mm long. Fruits 1.7 cm long, 0.5 cm diameter, ellipsoid, color unknown; endosperm ruminate.
A new species described in 2008 from central Vietnam. Pinanga humilis differs from all previously described species of Pinanga from Vietnam by its leaf sheaths which do not form a distinct crownshaft and inflorescences which are not infrafoliar. In this it is similar to P. cattienensis, differing in its distichously (versus spirally) arranged triads; 38–39 cm long (versus 90–95 cm long) rachis; and 5–7 (versus 9–13) pinnae per side of the rachis.
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