Epilobium williamsii P.H.Raven, 1962

Luo, Yike & Xie, Lei, 2023, A checklist of Onagraceae in the Pan-Himalaya region, Phytotaxa 597 (4), pp. 245-268 : 262

3.35. Epilobium williamsii P.H.Raven ( Fig.3D ).

Type:— NEPAL. Taglung, south of Tukucha , Kali Gandaki, approximately 28°39’N, 83°38’E, 3800 m, open grass slopes, 15 July 1954, Stainton, Sykes & Williams 1800 (holotype BM000957927 !, isotype E) .

= Epilobium ladakhianum Paul (1997: 197) , syn. nov.

Type:— INDIA. Jammu and Kashmir: Ganglas, Khardung La (Ladakh), 8 August 1988, Chowdhey & Uniyal 86083 (holotype BSD) ( Paul 1997).

Distribution: —U Ganga & Indus, C Nepal, E nepal, Bhutan, M Yarlung Zangbo, L Yarlung Zangbo, Yarlung Zangbo-Brahmaputra, S Hengduan, N Hengduan.

Note: —This species is most similar to Epilobium chitralense , from which it can be distinguished by the predominantly glandular pubescence of its inflorescence. Paul (1997) published E. ladakhianum as a new species. He wrote in diagnosis that E. ladakhianum has smaller petals (3.5–4 mm) and shorter stem (less than 7 cm) than E. williamsii . However, E. williamsii with 4–17(–25) cm tall stems, and 3–4.5 mm long sepals ( Chen et al. 2007). These characteristics are all within the range of character variation of E. williamsii . So, we reduced E. ladakhianum as a synonym of E. williamsii .

Figures

FIGURE 3. Field photographs of Epilobium. A: Epilobium parviflorum, shows the 4-lobed stigma. B: Epilobium sikkimense, shows the entire stigma. C: Epilobium wallichianum. D: Epilobium williamsii. Photographed by Y.K. Luo & L. Xie.