Roscoea purpurea KW.13755

Roscoea purpurea KW.13755

Archive entry 24.06.07

	This form was given an Award of Merit by the RHS in 1946. Originally collected by Frank Kingdon Ward in Assam in 1938, and introduced as "R.procera". Jill Cowley included this collection in Roscoea purpurea and says: "The plant which later came into cultivation and which was called 'procera' was a Kingdon Ward collection from Assam, but the same form can be found in Bhutan. Kingdon Ward's field notes on his collection no. 13755 state: 'KW 13755 Roscoea purpurea? Height 4-6". The leafy stem bears a succession of large yawning flowers, white splashed purple on the lower lip. Forms large colonies on steep rocky pine covered slopes high above Dirang Dzong. 7000-8000ft.'. July 1938'. Strangely the specimen of this number at the Natural History Museum bears slightly different field notes: 'Assam, Orka La, 8000-9000ft', June 1938, Kingdon Ward 13755'. Whatever the correct collecting data may be, the subsequent history of Kingdon Ward's plant is recorded in 1948 in the Gardener's Chronicle. F. C. Wood of Worthing wrote that "This species, if species it can be called - was sent home under the number KW 13755. Plants raised by Colonel (F. C.) Stern (OBE, MC), at Highdown flowered well and the new introduction was granted an A.M. (Award of Merit) on July 2 1946. There is apparently some doubt in the mind of botanists as to whether R. procera merits specific rank or whether it should be regarded as a variety of R. purpurea." In her monograph, Jill Cowley favoured the latter option and described it as Roscoea purpurea forma alba, saying: (Differs from the typical form (forma purpurea in having flowers which are white with a labellum splashed deep purple rather than wholly pale purple or reddish."
23rd June 2006

In 2017 Yoshida, Yangzom and Newman described it as a new species, Roscoea megalantha. In their paper they say:

"During a botanical expedition to Merak in Trashigang district, easternmost Bhutan,carried out by the Blue Poppy Society, Japan, and the National Biodiversity Centre, Bhutan, in the summer of 2014, numerous plants of great scientific interest were encountered. Among them were two populations of a species of Roscoea Sm. that appeared to represent a new taxon.
In 2014, on the way from Samdrup Jongkhar to Trashigang, the first two authors sawsome beautiful plants of Roscoea with large, whitish flowers streaked and flashed with purple on the labellum, by a huge rocky cliff named Melong Brak (= mirror cliff) to the right of the road, on a hill at 2200 m altitude. Later, east of Trashigang, on the way from Chaling to Merak, more plants of the same Roscoea were encountered on mossy, stony, west- to south-west–facing slopes at 2800–3200 m altitude. The plants in both populations resembled Roscoea purpurea Sm. but did not seem to belong to this species.
Specimens of Roscoea purpurea collected in eastern Bhutan and nearby Arunachal Pradesh (formerly Assam) are to be found in a number of herbaria and have been recognised by earlier authors as somewhat divergent morphologically from Roscoea purpurea. Kingdon-Ward 11529 (BM) was collected at Nyukmadung in Arunachal Pradesh in May 1935, and Kingdon-Ward 13755 (BM) at Orka La, Arunachal Pradesh (often spelled Warge La in Bhutan) in June 1938.
When we examined our collections from eastern Bhutan and the specimens just cited, we were convinced that the plants in eastern Bhutan and adjacent Arunachal Pradesh were sufficiently distinct as to be a species clearly different from the related Roscoea purpurea.


18th June 2006	20th June 2006	20th June 2006	23rd June 2006	24th June 2007

References:

Flora of China Online, http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=200028432 , accessed 19.11.2024.

Cowley, Jill - The Genus Roscoea, Royal Botanic Gardens Kew 2007.

Dunlop, Gary - 'The Genus Roscoea', Bulletin of the Alpine Garden Society, Vol.76, Part.2 (2008).

Wilford, Richard - 'Roscoeas for the rock garden', Bulletin of the Alpine Garden Society, Vol.67, Part.1 (1999).

Wilford, Richard - 'Roscoea on trial', The Plantsman, Vol.11, Part.2 (2012).

Yoshida, T., R. Yangzom and M.F. Newman - 'Roscoea megalantha, a new species from Eastern Bhutan and India', Edinburgh Journal of Botany, Vol.74, Part.3 (2017).