Pinanga cupularis informazioni
Stems clustered, rarely solitary, to 2 m tall, 0.4–0.8 cm diam., densely covered with reddish-brown scales. Sheaths closed, forming a crownshaft, 6.5–12 cm long, densely covered with reddish-brown scales; ocreas 1.5–2 cm long; petioles 3.5–6 cm long, green with whitish scales; rachis 11.5–40 cm long; pinnae 2–4 per side of rachis, falcate, not contracted at the bases, middle pinna 10–15 cm long, 1–3 cm wide at the middle, apical pinna 4.5–5 cm long, 2–4 cm wide at the middle, lobed, rarely blade undivided, then blade 21 cm long and 8 cm wide at the middle; veins only slightly raised adaxially. Inflorescences infrafoliar, pendulous; peduncles 0.1–0.2 cm long, 0.2 cm wide; prophylls 5–6.5 cm long; rachis absent; rachilla 1, 3–6.4 cm long, rectangular in crosssection, glabrous; triads distichously arranged; staminate flowers 11 mm long; sepals forming a 3-lobed, flat, membranous calyx, 1.5 mm long; petals 10 mm long, irregularly lobed at the apices, one petal larger than the other two, fleshy, with 2 mm long, hyaline hairs at the apices; stamens 4; pistillate flowers 2.5 mm long; calyx 2.5 mm long, cupular, not split into 3 sepals, ciliate at the apices; corolla similar to the calyx; ovary 2.5 mm long; fruiting calyx briefly and irregularly split at the apices; fruits 1.2–2 cm long, 0.2–0.4 cm diameter narrowly ellipsoid, slightly curved, colour unknown; endosperm homogeneous.
A new species described in 2008 from Central Vietnam. This species was identified as Pinanga paradoxa Scheff. by both Magalon (1930) and Gagnepain and Conrard (1937), who also recorded it from Lao. It differs from that species, occurring in Thailand and West Malaysia, in its cupular (versus imbricate) pistillate perianth and narrow fruits 0.2–0.4 cm (versus 1 cm) diameter. It is an unusual species of Pinanga in its staminate petals with long hairs on the apices, 4 stamens, cupular pistillate perianth, and homogeneous endosperm. Amongst Vietnamese species it most resembles P. kontumensis. It differs from this in its pendulous (versus erect) inflorescences, and cupular (versus free and imbricate) pistillate perianth.