19. Lanonia verrucosa Henderson & Nguy ễn Quốc Dựng (2017: 163). Type:— VIETNAM. Khanh Hoa province, Ninh Hoa district, Ninh Tay commune, road to hydroelectric dam, 12°35’N 108°58’E, 433 m, 7 October 2016, A. Henderson & Nguyễn Qu ốc Dựng 4079 (holotype VFM!, isotype NY!) .

Stems 1.5 m long, 6.0 cm diameter,solitary. Leaves number not recorded; ligules not recorded;sheaths and proximalmost part of petioles with scattered, brown scales; petioles 130.0 cm long, 0.8 cm wide at the apex; petiole thorns usually poorly developed, brown or black, more or less regularly arranged on proximalmost part of petiole; hastulas raised, triangular, infolded; leaf blades 80.0 cm wide; costas 17.0 cm long, narrow, with a pulvinus at the apex abaxially, with the few segments free except the middle pair joined at their bases; segments 7 per leaf, not mottled, with minute, reddish-brown scales abaxially, with (on dried specimens) straight margins; middle segments 43.0 cm long, 18.0 cm wide at the apex; apices of middle segments with adaxial splits not much deeper than abaxial ones. Inflorescences length not recorded; prophylls and peduncles length not recorded; rachis bracts flattened, splitting apically and laterally, usually densely brown tomentose; rachillae not filiform nor thick and ribbed, sparsely to moderately covered with short, mostly simple, brownish hairs; staminate inflorescences rachises, number of partial inflorescences, branching, and number of rachillae not recorded; staminate rachillae 11.5 cm long, 0.9 mm diameter; staminate flowers 3.0 mm long; sepals pedicellate at the base, not densely hairy; petals rounded at the apex; stamens with equal filaments and longer, rectangular anthers; filaments not elongate; pistillodes undivided; pistillate rachises absent; pistillate partial inflorescences 1, branched to 3 orders; pistillate rachillae on proximalmost partial inflorescence 11, 16.5 cm long, 1.6 mm diameter; pistillate flowers length and styles not recorded; fruits 8.9 mm long, 7.2 mm diameter, ellipsoid, orange, with uneven, ridged surfaces; seeds with a curved basal intrusion.

Distribution and habitat:—Southern Vietnam in Khanh Hoa province in disturbed forest on steep, rocky slopes at 433 m elevation (Fig. 17).

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

Lanonia verrucosa appears similar to L. acaulis and L. dasyantha, sharing with those species ellipsoid fruits with uneven, ridged surfaces. It differs from these species in its non–mottled (versus mottled) leaves, slender (versus thick and ribbed) rachillae, pedicellate (versus non-pedicellate) staminate sepals, and staminate petals with rounded (versus narrowed) apices.