Sorbus foliolosa vs Sorbus microphylla

[J.M. Garg]

Due to confusion on the net, trying to figure out the difference between the two as per Flora of China description:
Sorbus microphylla (Wallich ex J. D. Hooker) Wenzig

Shrubs or small trees, 2–5 m tall. Branchlets reddish brown when young, grayish brown when old, terete, puberulous when young, with sparse, oblong or suborbicular lenticels; buds conical or ovoid, 5–7(–8) mm, apex acuminate and puberulous; scales several, reddish brown. Leaves imparipinnate, together with rachis 11–14 cm; petiole 1–1.5 cm; stipules lanceolate or subulate-lanceolate, 4–6 mm, submembranous, margin entire or slightly 2-lobed; rachis slender, adaxially grooved with reddish glands at base of leaflet, ± brown puberulous, glabrous when old, narrowly winged; leaflet blades 10–17(–19) pairs, at intervals of 5–8 mm, pale abaxially, dark green adaxially, linear-oblong, 0.7–1.5(–2) cm × 4–8 mm, both surfaces glabrous, or abaxially with brown hairs only along midvein when young, base obliquely rounded, margin sparsely sharply serrate, apex obtuse or acute. Compound corymbs terminal, 2–4(–6) cm, laxly flowered; rachis and pedicels glabrous, rarely brown puberulous; bracts narrowly lanceolate, smaller than stipules, submembranous. Pedicel 6–9 mm. Flowers 7–10 mm in diam. Hypanthium dark purplish black, broadly campanulate, 2–3 mm, glabrous. Sepals triangular, 1.5–2 mm, apex acute, rarely ± obtuse. Petals pink, suborbicular, 3–4 mm, glabrous, base shortly clawed. Stamens ca. 20, slightly shorter than petals; filaments rose; anthers nearly purplish black. Styles 5, ca. as long as stamens, pubescent basally. Fruit white or flushed pink or crimson, globose or ovoid, 8–10(–12) mm in diam., glabrous, without lenticels, with persistent erect sepals; seeds blackish, oblong-ovoid, 3–4 mm. Fl. May–Jun, fr. Sep–Oct.
Forests or shrubby thickets in valleys or along river banks; 3000--4000 m. E Xizang (Gongbo’gyamda Xian), NW Yunnan [Afghanistan, Bhutan, NE India, N Myanmar, Nepal, Pakistan, Sikkim].

Sorbus foliolosa (Wallich) Spach
Shrubs or small trees, 1–4 m tall. Branchlets brownish to grayish brown, terete, densely rusty pubescent when young, glabrescent, with oblong lenticels; buds ovoid, 4–6 mm, apex obtuse; scales several, brown, glabrous or rusty puberulous apically. Leaves imparipinnate, together with rachis 7–12 cm; petiole 1.5–2 cm; stipules caducous, linear-lanceolate, 4–8 mm, margin entire or serrate; rachis shallowly sulcate, slightly rusty puberulous, narrowly winged; leaflet blades (4–)6–9 pairs, subleathery, at intervals of 0.8–1.2 cm, dark green adaxially, oblong-elliptic or oblong, 2–3.5(–4.5) × 0.8–1.4 cm, lateral veins slender, abaxially slightly pubescent, rusty puberulous or subglabrous along midvein, glabrous, rarely pubescent, base obliquely rounded, margin sharply few toothed apically. Compound corymbs 4.5–10 cm in diam., many flowered; rachis and pedicels with rusty hairs and oblong lenticels; bracts caducous, linear, 1–3 mm. Pedicel 1–2 mm or indistinct. Flowers 6–9 mm in diam. Hypanthium campanulate or obconic, glabrous or slightly pubescent. Sepals triangular, glabrous, apex obtuse or acute. Petals white, ovate to broadly obovate, 2–3 mm, base shortly clawed. Stamens 20, shorter than petals. Styles 2 or 3(or 4), free at base, glabrous. Fruit red, globose or ovoid, 4–6 mm in diam., with sparse small lenticels; sepals persistent; seeds brownish, 1–2 mm. Fl. Apr–Jun, fr. Sep–Oct. 2n = 68.
Mixed forests, stream sides; 2500--4200 m. SE Xizang, Yunnan [Bhutan, N India, N Myanmar, Nepal, Sikkim].

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With regards,
J.M.Garg