1. Sapindus chrysotrichus Gagnepain (1947: 67) (Figure 19).

Lectotype (designated here):— VIETNAM. Ninh Tu ận: Phanrang, Ba-Rau, 19 February 1924, E. Poilane 9640 (P06693106!; isolectotypes, A01771320!, P06693108!).

Etymology:—Probably in reference to the golden yellow hairs on various plant parts.

Description:—Tree, 10–13 m tall, bark not observed. Petiole 0.8–2.2 cm long, pubescent, gray, unwinged; rachis moderately pubescent on the upper side, unwinged; leaflets 2–4; petiolule 0–2 mm long, moderately pubescent on the upper side; leaflet blade ovate to ovate-elliptic, symmetric or nearly so, straight to scarcely falcate, the apex rounded to obtuse, 3–12 cm long, 2–5 cm wide, 2–3.5 times longer than wide, adaxially pale green to pale brown-green, glabrous to pubescent along the midrib, often strongly papillate along the midrib, midrib pale green to pale yellow, at mid-blade the ridge 0.1-0.3 mm high, 0.1-0.3 mm wide, blade not sunken along the midrib, secondary veins pale green to pale yellow, discolorous with the blade surface, tertiary venation scarcely raised, nearly obscure, quaternary venation obscure, abaxially pale green to pale brown-green, glabrous, along the midrib proximally pubescent, secondary veins prominent, discolorous with the blade surface, tertiary, quaternary, and quinternary venation raised, conspicuous, concolorous with the blade surface; exudates clear to slightly golden and clear, inconspicuous abaxially on the leaflet blade surface. Petal with 2 appendages. Mature mericarp 15–20 mm wide, pubescent, seed 12–15 mm wide.

Distribution, habitat, and phenology:— Vietnam (Fig. 4); 0–1000(?) m. Forest. Flowering time unknown.

Notes:— This species has a pubescent ovary, like S. sonlaensis, also from Vietnam. The petiolules are exceptionally woody. The lectotype chosen here has a detailed illustration of the flower parts attached to the sheet. The species was illustrated by Gagnepain (1950: 945).

Conservation Status:—Only two collections are known for this species, both from the same collector in 1924. The species was also reported by Nguyen (2002). It is difficult to speculate the extent of its suitable habitat. Its total population cannot be reliably estimated. Therefore, the category of Data Deficient (IUCN 2012) seems most appropriate at this time.

Specimens examined:— VIETNAM. Ninh Tu ận: Phanrang Province, Trai ca, 11 March 1924, Poilane 10068 (P [2 sheets]).