2. Lanonia batoensis Henderson & Nguy ễn Quốc Dựng (2017: 159). Type:— VIETNAM. Quang Ngai, Ba To District, road from Ba To to Ba Cung, 14°44’N 108°53’E, ca. 600 m, 18 July 2012, A . Henderson, Nguyễn Qu ốc Dựng & Le Van Tuan 3818 (holotype VFM!, isotype NY!) .

Stems 1.8 m long, 3.0 cm diameter, solitary. Leaves 12 per stem; ligules 1.6(1.5–1.7) cm long, soon disintegrating into fibers; sheaths and proximalmost part of petioles without scales; petioles 85.0 cm long, 0.6(0.5–0.7) cm wide at the apex; petiole thorns usually poorly developed, brown or black, more or less regularly arranged on proximalmost part of petiole; hastulas flat, rounded, not infolded; leaf blades 65.0 cm wide; costas 3.2(3.0–3.3) cm long, triangular, with a pulvinus at the apex abaxially, with the numerous segments free almost to the base; segments 20(19–20) per leaf, not mottled, without minute, reddish-brown scales abaxially, with (on dried specimens) straight margins; middle segments 52.0(50.5–53.5) cm long, 1.3(1.0–1.6) cm wide at the apex; apices of middle segments with adaxial splits much deeper than abaxial ones. Inflorescences 122.5(115.0–130.0) cm long; prophylls and peduncles length not recorded; rachis bracts tubular, splitting apically, not densely tomentose; rachillae not filiform nor thick and ribbed, sparsely to moderately covered with short, mostly simple, brownish hairs; staminate rachises not recorded; staminate partial inflorescences 6, branched to 3 orders; staminate rachillae number and length not recorded, 0.9 mm diameter; staminate flowers not recorded; pistillate rachises absent; pistillate partial inflorescences 1, branched to 3 orders; pistillate rachillae on proximalmost partial inflorescence 18, 18.4 cm long, 1.3 mm diameter; pistillate flowers length and styles not recorded; fruits not recorded; seeds not recorded.

Distribution and habitat:—Central Vietnam in Quang Ngai province, Ba To District, in lowland rainforest at 600 m elevation (Fig. 8).

Taxonomic notes:— Specimens determined as preliminary species Lanonia batoensis share a unique combination of qualitative variable states and are therefore recognized as a phylogenetic species.

Lanonia batoensis is notable for its sheaths and proximalmost part of petioles without scales, narrow leaf segments without minute, reddish-brown scales abaxially, large, erect inflorescences projecting above the leaves, and tubular, apically splitting, not densely tomentose rachis bracts.