Table 1.

Morphological comparison of species of Oxalisxishuiensis and its relatives.

Characters	O.xishuiensis	O.wulingensis	O.acetosella	O.griffithii
Rhizomes (including scales)	Ca. 10 mm in diameter	Ca. 10 mm in diameter	Ca. 3 mm in diameter	6–12 mm in diameter
Two lateral leaflets arrangement	About 180° angle	180° angle	120° angle	120° angle
Leaflets	Two lateral leaflets obliquely obcordate, 1.4 –2.1 × 1.3–2 cm; middle leaflets obcordate, 2–3.1 × 1.9–3 cm	Long obtriangular, 2.2–3.1 × 1.6–2.5 cm	Obcordate, 0.5–2 × 0.8–3 cm	Obtriangular, 1–2.5(–4.5) × 1.5–3.5(–5.5) cm
Leaflet apex	Broadly emarginate	Broadly emarginate	Deeply emarginate	Broadly emarginate to subtruncate
Leaflet indumentum	Both surfaces white pubescent or adaxially glabrous	Both surfaces villous (densely covered with long, brown hairs)	Both surfaces pubescent	Abaxially pubescent, adaxially glabrous
Leaflet adaxial surface colour	Light green to green	Green	Green	Green
Leaflet abaxial surface colour	Pale green, purple when young	Purple	Whitish-green, purple or red	Pale green or green
Peduncles in flowering	Ca. 3–4 cm long, shorter than leaves	10–12 cm long, longer than leaves	Peduncle equal to or longer than leaves	4–15 cm long, equal to or longer than leaves
Petal	Oblong ca. 2 cm, apex obtuse or irregularly denticulate	Oblong ca. 2.5 cm, apex obtuse or irregularly denticulate	Obovate, (1.2–)1.5–2.2 cm, apex retuse to deeply emarginate	Narrowly obovate, 1.2–1.6 (–2) cm, apex retuse to deeply emarginate
Petal colour	Pink with lilac veins	Pink with lilac veins	White, lilac to pinkish veined	White, rarely pink (Hubei)
Capsules	Ovoid or oblong, 12–15 × 4–5 mm	Ovoid, 5–7 mm long	Ovoid, 3–4 mm	Oblong-conic, 5–13 × 5–6 mm
Seed	Ovoid, ca. 3 mm long, with longitudinally ridge and alveolate	Ovoid, ca. 2.1 mm long, with longitudinally ridge	Ovoid, with longitudinally ridged	Ovoid, 2.5–3.5 mm, with longitudinally ridged
Flowering time	Chasmogamous flowers: February to March, Cleistogamous flowers: May to June	March	July to August	March to September