Bambusa thorelii

Local name: No known records.

Distribution: THAILAND: It is not known whether specimens have been collected on the Thai side of the Mekong River, or elsewhere since the original collection. — LAOS: The location of the collection of the type specimens of Bambusa thorelii is "Kang" (É. G. Camus, Les Bambusées (1913), p. 136). A location name in that spelling could not be identified on the available temporary and historical maps. It is assumed that "Kang" is a French phonetic transcription of the location name, and it actually sounds like [kʰɔːŋ] (IPA phonetic symbols). There is one location, usually named "Khong" on maps, in ຈໍາປາສັກ (Champassak) Province of southern Laos: ດອນໂຂງ (Don Không, don = island), and ເມືອງໂຂງ (Muang Không, muang = fortified city) or in Thai เมืองโขง (Mueang Khong). It could be that the specimens were collected on that large island ໂຂງ (Không) of the Mekong River, as this would fit well with the collection year and route of the expedition. Further, the distribution of Bambusa thorelii was assumed to extend along the Mekong River from Nong Khai (northern North-East of Thailand) to Ubon Ratchathani (southern North-East of Thailand) in both the Thai and Laotian areas, but there is not any single record known that would support this speculative assumption. The specimens of Bambusa thorelii were collected in 1866 by C. Thorel during the French "Expédition du Mè-Khong" (1866-1868), which went upstream Mekong River by a gunboat (Francis Garnier, Voyage d'exploration en Indo-chine, effectué pendant les années 1866, 1867 et 1868, 2 volumes, Paris, 1873; rééd. La Découverte, 1985 (ISBN 270711409X)). Many specimens were collected during that expedition in the first year (1866) in Stung Treng (Khmer: ស្ទឹងត្រែង, Lao: ຊຽງແຕງ, Thai: เชียงแตง Chiang Taeng) located on the Mekong River, and nowadays part of Cambodia. As Bambusa thorelii was found in the same year, the collecting area could not be too distant from Sung Treng. A nearby area upstream was the former Kingdom of ຈໍາປາສັກ (Champassak, under the suzerainty of the Kingdom of Siam, and nowadays a southern part of Laos), but it was not an occupied area by the French at the time of the expedition. As the expedition went further upstream, the specimens of Bambusa thorelii could have been collected on the banks of, or on an island in the Mekong River in present-day Laos. It is therefore justified and advisable to first search for possible rediscoveries of this species, Bambusa thorelii. on Kong Island.

Culm size: No known records.

Images: Line drawing in É. G. Camus, Les Bambusées, Atlas, 1913, pl. 100; photos in Herb. Mus. Paris (culm sheath, flowers) [#1334].

Comments:

(1) Flowers known.

(2) The species name is considered an "unresolved" name by The Plant List.

(3) The photo of the culm sheath (Herb. Mus. Paris) shows a close similarity with the culm sheaths of ×Thyrsocalamus liang, syn. Bambusa nana hort., Thai common name ไผ่เลี้ยง (phai liang). However, the spikelets in the line drawing of Bambusa thorelii are small, whereas in ไผ่เลี้ยง (phai liang) the spikelets are known to be larger. A closer look at the photographs of the type specimens was taken: The pseudospikelets of Bambusa thorelii are 5–6 mm long only, whereas those collected from phai liang are double-sized, 10–12 mm long. This rules out that Bambusa thorelii and phai liang are conspecific. (K. M. Wong, pers. comm., 24 Mar. 2016).