24. Pilea chartacea C. J. Chen, Bull. Bot. Res., Harbin. 2(3): 63. 1982.
纸质冷水花 zhi zhi leng shui hua
Pilea velutinipes Handel-Mazzetti, p.p.
Herbs perennial, stoloniferous, glabrous, dioecious or sometimes monoecious. Stems often reddish, stramineous when dry, simple or few branched, angled, 30-40 cm tall, succulent, with galls on mid portion of internodes. Stipules persistent, brownish, narrowly ovate, 3-4 mm, membranous, acute at apex; petioles subequal in length, 0.7-1.5 cm; leaf blade abaxially pale green, adaxially dark green, rugulose, elliptic-lanceolate, subequal in size, 3-7 × 1.2-2.3 cm, papery, prominently 3-veined on both surfaces, lateral veins several, irregular, inconspicuous, adaxial surface reddish squamulose, with linear cystoliths along margin, base broadly cuneate or obtuse, margin shallowly serrate, apex acuminate. Male inflorescence a cyme, 1-1.5 cm; pedunculate, female cymes often compacted into clusters, ca. 0.7 cm, subsessile or shortly pedunculate. Male flowers pedicellate, in bud ca. 2.5 mm; perianth lobes 4, oblong, subapically corniculate; stamens 4; rudimentary ovary small, conic. Female flowers subsessile; perianth lobes connate at base, unequal, abaxial lobe cymbiform, longer, subapically corniculate; staminodes 3, scale-like, oblong. Achene greenish brown, obliquely ovoid, ca. 1 mm, slightly compressed, verrucose. Fl. and fr. Mar.
* Shaded wet places along streams; below 200 m. Guangdong [?Vietnam].
Other syntype material of Pilea velutinipes belongs to species 20, P. aquarum (subsp. aquarum).