a mon avis, aucune chance que ce soit B. rockii, c'est un nom utilisé pour n'importe quoi en particulier des hybrides type rex
voila la description de rockii
good luck, Reiner
Herbs. Rhizomes elongate, 9–14 mm in diam. Leaves
basal; stipules triangular-ovate, 5–16 × 3–10 mm, abaxially
remotely pubescent, apex acute; petiole 3–20 cm, rusty hairy;
blade abaxially reddish, abaxially dark green with brownish irregular
fine spots, sometimes with white spots between main
veins, broadly ovate, asymmetric, 5.5–30 × 3.5–20 cm, abaxially
hispid, adaxially hispidulous, venation palmate, 6- or 7-
veined, base strongly oblique, cordate, margin remotely and minutely
serrulate, ciliate, apex acute or obtuse. Inflorescences
sparsely hairy; bracts ovate-oblong, 5–8 × 3–5 mm, abaxially
pilose, margin ciliate, apex obtuse or acute. Staminate flowers:
pedicel 1–1.8 cm; tepals 4, white, outer 2 broadly ovate or orbicular,
1–1.9 × 0.7–1.4 cm, abaxially scabrescent, inner 2 obovate,
8–17 × 6–10 mm; stamens ca. 120; filaments 1–6.1 mm,
fused at base; anthers obovoid-globose, 1–1.4 mm, apex truncate
or emarginate. Pistillate flowers: pedicel 0.9–1.1 mm; tepals
5, white, unequal, broadly ovate to oval, largest 6–10.5 ×
4.4–9.1 mm, abaxially scabrescent, smallest 4.5–9.5 × 3.5–4.7
mm; ovary elliptic, scabrescent, 2-loculed; placentae axile, bilamellate;
styles 2, 2–6.2 mm, fused to halfway; stigmas 2-cleft,
spiraled. Capsule nodding, unequally 3-winged; abaxial wing
ligulate, ca. 1.6 × 1.2 cm, apex rounded; lateral wings 5.2–6.6
mm. Fl. Nov.
Forests, rock faces; 700–800 m. Yunnan (Yingjiang) [Myanmar].