Licuala caespitosa Henderson & Nguyen Quoc Dung, 2017

Henderson, Andrew & Dung, Nguyen Quoc, 2017, New species of Lanonia, Licuala, and Pinanga (Arecaceae) from Vietnam, Phytotaxa 323 (2), pp. 159-172 : 164

Licuala caespitosa Henderson & Nguyen Quoc Dung sp. nov. ( Fig. 5 )

Type:— VIETNAM. Da Nang City, Hoa Vang District, Ba Na-Nui Chua Nature Reserve, road to summit, 16°00’N, 108°02’E, ca. 350 m elevation, 20th April 2017, A. Henderson & Nguyen Quoc Dung 4211 (holotype VFM!, isotype NY!).

It differs from the similar Licuala glaberrima in its clustered (versus solitary) stems, solitary or paired flowers (versus solitary), and tubular calyces (versus calyces with pedicellate base).

Stems clustered, to 3.0 m tall, 5.0 cm diameter. Leaf number not recorded; sheaths not recorded; ligules prominent, to 55.0 cm long; petioles to 165.0 cm long, thorny for only about 30.0 cm proximally with short thorns to 0.5 cm long; blades to 95.0 cm across, split into 28-32 segments, these with straight sides; costa continuous into central segment, forming a petiolulate base to segment; middle segment 52.0 cm long, 4.5 cm wide at apex; lateral segment 35.0 cm long, 0.5 cm wide at apex; segments briefly indented at the apex, and with minute, brown scales abaxially. Inflorescences erect amongst the leaves, to 120.0 cm long, branched to 2 orders; prophylls not recorded; rachis bracts elongate, tubular, ca. 20.0 cm long; partial inflorescences 3; rachillae glabrous, to 19.0 cm long; flowers 3.0 mm long, mostly solitary, a few paired on proximal parts of rachillae, distantly and spirally arranged, yellow at anthesis; calyx 2.0 mm long, glabrous, tubular, scarcely lobed at the apex; corolla 3.0 mm long, glabrous, split for ca. two thirds its length into 3, valvate petals; stamens 6; staminal ring 0.5 mm high; filaments free for 0.7 mm; anthers rounded, 0.5 mm long; pistil 1.5 mm long including a 0.7 mm long style, glabrous; fruits not recorded.

Distribution and habitat:—Central Vietnam in Ba Na-Nui Chua Nature Reserve in lowland rainforest on steep slopes at 350 m elevation.

Taxonomic notes:— Licuala caespitosa is known from only a single specimen from Ba Na-Nui Chua Nature Reserve. It is similar to L. glaberrima , differing in its larger size, clustered stems, solitary or paired flowers, and tubular calyces. Licuala glaberrima occurs over 400 km further to the south in Khanh Hoa province.

Figures

FIGURE 5. Licuala caespitosa. Left, habit. Right, leaf bases with prominent ligules (from Henderson & Nguyen Quoc Dung 4211).