Two new species of Oreocharis in Vietnam 
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Table 1. Characteristics distinguishing Oreocharis argyrophylla, O. argyreia and O. hirsuta. 
Characters 
O. argyrophylla 
O. argyreia 
O. hirsuta 
Leaf hairs 
Densely appressed 
silvery pubescent 
Densely appressed 
silvery pubescent 
Sparsely spreading 
hirsute 
Corolla 
Yellow, narrowly 
infundibuliform, 2.5- 
3.1 cm 
Blue-purple to purplish 
white, nearly cylindrical, 
2-2.3 cm 
Yellow, nearly 
cylindrical, 2-2.9 cm 
Corolla tube 
1.7-2.2 cm long, 2.8- 
3 mm in diam. at base, 
6-2.8 mm in diam. at 
throat 
1.5-2 cm long, almost 
0.5-0.6 cm in diam. from 
base to top 
1.6-1.9 cm long, 4-5 
mm in diam. from base 
to top 
Corolla limb 
Distinctly 2-lipped, 
lips unequal; 
Slightly 2-lipped, lips 
subequal; 
Weakly 2-lipped, lips 
unequal. 
Adaxial lip 
Lobes oblong, 5.8-6 x 
4.1-4.3 mm 
Lobes suborbicular, 2- 
3 mm in diam. 
Lobes ovate, 7.6-8 x c. 
5 mm 
Abaxial lip 
Lobes oblong, subequal, 
middle 7.4-7.5 x 6.1-6.2 
mm, lateral lobes 7-7.1 
x 4.4-4.7 mm 
Lobes suborbicular, 
equal, 2-3 mm in diam 
Lobes ovate, subequal, 
middle 7.6-8 x 
6.7-7 mm, lateral lobes 
7.2-7.7 x 6-6.1 mm. 
Anthers 
Coherent in 2 pairs 
Not coherent 
Not coherent 
humid forests on very steep mountain slopes composed of shale and sandstone at 
elevations of 1000-1850 m. This species is only known from the Xuan Nha nature 
reserve, Son La province of north-western Vietnam, where it is common. Flowering in 
September-December and fruiting in October-December. 
Provisional IUCN conservation status. Endangered EN Blab(ii,iii,v) + B2ab(ii,iii,v), 
following IUCN (2012, 2016) guidelines. This is based on an EOO of < 5000 km 2 
and an AOO of < 500 km 2 , being known from fewer than five populations, and with 
evidence of a reduction in the area of occupancy, a decline in habitat quality, and a 
decline in the number of individuals due to deforestation, largely for agriculture and 
due to fire. 
Additional specimens examined. VIETNAM. Son La: Van Ho district, Chieng Xuan municipality, 
Co Hong village, territory of Xuan Nha nature reserve, Pha Luong Mountain, 13 Nov 2013, in 
fruit, Averyanov, L. et al. CPC 7020 (CPC, KUN, LE); Moc Chau Distr., Chieng Son comm., 
Pha Luong vill., Pha Luong Mountains, 1400-1500 m a.s.L, 20°41'33.2"N 104°37'37.0"E, 22 
Sep 2016, Averyanov, L. et al. CPC 7939 (CPC, LE); Moc Chau Distr., Chieng Son comm., 
Pha Luong vill., Pha Luong Mountain, 20°40'23.0"N 104°37'52.0"E, 1750-1850 m a.s.L, 23 
Sep 2016, Averyanov, L. et al. CPC 7993 (CPC, LE); Moc Chau Distr., Chieng Son comm., Pha 
Luong vill., Pha Luong Mountain system, 20°4L30.9"N 104°38'08.9"E, 1425 m a.s.L, 25 Sep 
2016, Averyanov, L. et al. CPC 8026 (CPC, E); Van Ho Distr., Tan Xuan comm., A Lay village, 
around point 20°40'46.2"N 104°39'49.6"E, approx. 1500 m a.s.L, 1 Oct 2016, Averyanov, L. et 
al. CPC 8173 { CPC, PE). 
