4a. Veronicastrum stenostachyum subsp. stenostachyum
腹水草(原亚种) fu shui cao (yuan ya zhong)
Calorhabdos stenostachya Hemsley in F. B. Forbes & Hemsley, J. Linn. Soc., Bot. 26: 196. 1890; C. fargesii Franchet; C. venosa Hemsley p.p. excluding syntype from Zhejiang.
Stems more than 1 m, mostly arching and rooting apically, rarely erect, angular, glabrous. Leaf blade narrowly ovate to lanceolate. Inflorescences axillary, sometimes terminal on leafy branches, rarely also on main stems. Bracts and calyces shorter than or rarely as long as corolla, sparsely ciliate. Corolla white, purple, or purple-red. Fl. Jul-Sep.
* N Guizhou, W Hubei, NW Hunan, S Shaanxi, Sichuan (E of Erlang Shan).
This subspecies is variable and may be polytypic. Plants from S Shaanxi and NE Sichuan have usually broader leaves and bracts and more coarsely dentate leaf margin, while those
from Emei Shan and Ya án have narrower, lanceolate to ovate-lanceolate leaves and sparsely flowered inflorescences also terminal on main stems.