Zingiber bambusifolium subsp. bambusifolium

Zingiber bambusifolium subsp. bambusifolium 乌姜 (wū jiāng) Fig. 1C–D View FIGURE 1 & Figs. 2–4 View FIGURE 2 View FIGURE 3 View FIGURE 4 .

≡ Tupistra bambusifolia H.Lév. & Vaniot View in CoL in Mem. Pontif.Accad. Romana Nuovi Lincei 24: 349. 1906 — Lectotype (designated by McKean in Notes Roy. Bot. Gard. Edinburgh 44(1): 176. 1986, corrected from “holo”): CHINA. Kouy-Tchéou, Pin-Fa [Guizhou Province, Qiannan Buyi & Miao Autonomous Prefecture, Guiding County], 8 Sep 1903, J. Cavalerie 1360 (E [barcode E00265088 -image!]; isolectotype: P [barcode P00450986 - image!]).

= Zingiber lingyunense D.Fang View in CoL in Acta Phytotax. Sin. 18(2): 226. 1980, syn. nov.— Lectotype (designated by Bai & al in Taxon 73: 595. 2024): CHINA. Guangxi Province, Lingyun County, Xiajia Gongshe , Shuilu Dadui , Shuilu Hamlet [Xiajia Village, Shuilu Hamlet], 22 Aug 1978, D.H. Qin, S.Z. Luo & B.G. Yang 19803 (GXMI [barcode GXMI 051064 About GXMI !]; isolectotypes: GXMI [barcode GXMI 051065 About GXMI !], IBSC [barcode 0005290!], PE [barcodes 00033340! & 00033341!]).

Other specimens examined:— CHINA. Guangxi Province: Baise City, Leye County, Gantian Village elev. 1070 m, 28 June 1959, C. T. Li 603237 ( IBK [barcode IBK 00137769]); ibidem, 24 September 1977, Leye Expedition 3- 30138 ( GXMI [barcode GXMI 045423]); ibidem, elev. 1070 m, 4 November 2023, L. Bai et al. BLSC-326 ( IBSC); Baise City, Leye County, Huaping Village, 12 September 2013, H. Z. Lv et al. 451028130912001 LY ( GXMG [barcode GXMG 0098453]); Baise City, Leye County, Tongle Village, 6 November 2012, Y. M. Zhao et al. 1976 ( GXMG); Baise City, Leye County, Yazhang Village, elev. 699 m, 25 July 2014, Z. C. Lu et al. YC0677 ( IBK); ibidem, elev. 1028 m, 24 October 2014, Z. C. Lu et al. YC1157 ( IBK); Baise City, Lingyun County, Xiajia Village, 12 October 1977, K. Z. Yuan 3-26101 ( GXMI barcode GXMI 051066); Baise City, Tianlin County, Langping Village , 20 September 1977, Tianlin Expedition 3-43328 ( GXMI [barcode GXMI 045421]); Hechi City, Fengshan County, Jinya Village , elev. 2000 m, 21 September 1977, Fengshan Expedition 40 ( GXMI [barcode GXMI 045422]). Guizhou Province: Qiannan Buyi & Miao Autonomous Prefecture, Guiding County, Yunwu Village, elev. 980 m, 27 July 2024, L. Bai & Y. Y. Zhang BLSC-24072803 ( IBSC).

Ecology & Phenology:— Zingiber bambusifolium subsp. bambusifolium grows in understories of carbonate rock-based (limestone or dolomite) soil. Rhizomes are often covered by thick litter layers. The elevation of occurrence is between 699 m to 2000 m. Flower records are from late-July to late August. Fruits start to mature from September but last till early November.

Distribution & Conservation status:— Zingiber bambusifolium subsp. bambusifolium is currently known from Baise City and Hechi City in Guangxi Province and Qiannan Buyi & Miao Autonomous Prefecture of Guizhou Province ( Fig. 5 View FIGURE 5 ). The Extent of Occurrence (EOO) is about 11500 km 2. In the two spots I collected the subspecies in Leye County in Guangxi Province and Guiding County in Guizhou Province, the species forms rather large populations. At present, I therefore propose to treat Z. bambusifolium subsp. bambusifolium as ‘Least concerned’ (LC) according to the latest IUCN Criteria (IUCN 2012, 2019).

Etymology:— The specific epithet “ bambusifolium ” is derived from the narrow laminae that resemble bamboo leaves.

Notes:— The presence of minute, circular or oblong, dark brown punctae on upper surface of laminae on type specimens of T. bambusifolia var. bambusifolia is a critical character in resolving its identity. These punctae appear to be natural pigmentation. They are visible with the naked eye on dry specimens (see Fig. 1D View FIGURE 1 & 2B View FIGURE 2 ). They also occur on several other species of Z. sect. Cryptanthium that have a burgundy red tinge (when fresh) on the lower surface of their laminae, e.g. Z. cochleariforme Fang (1980: 225) , Z. guangxiense Fang (1980: 226) (unpublished data). These punctae do not show on a light microscope leaf epidermis examination after regular pretreatment of removing mesophyll cells. Nor do they show under scanning electron microscope (SEM) either. Coincidentally, Léveillé (1906) named T. bambusifolia var. rubromaculosa (rubro+ maculosus, meaning red spotted or red blotched), after the irregular, diffused brownish patches (“Feuilles tachées de rouge”) that appear on the lamina of the type specimens ( Fig. 1B View FIGURE 1 ). However, those patches are not punctae; they are probably caused by fungi.

During the search for Z. bambusifolium subsp. bambusifolium from its type locality, three other species of Z. sect. Cryptanthium, viz. Z. atrorubens , Z. emeiense Zhu (1984:185) , and Z. tuanjuum Zhu (1984:187) , were found in the general area. They all differ from Z. bambusifolium subsp. bambusifolium by their lack of the minute, circular or oblong, dark brown punctae on upper surface of lamina on dry specimens. Zingiber atrorubens (= T. bambusifolia var. rubromaculosa ) futher differs from Z. bambusifolium subsp. bambusifolium by the labellum being pink to violet with white striae (vs cream-coloured), lateral staminodes being absent or vestigial (vs lateral staminodes prominent) and leaf sheaths being partially closed (vs open). Zingiber tuanjuum futher differs from Z. bambusifolium subsp. bambusifolium by having longer ligules (10–30 mm vs 1–6 mm), larger laminae (30–41 × 3.4–6.5 vs 14–27 × 1.8–3.5 cm) and larger bracts (2.5–5.7 × 1.2–3.5 cm vs 2.5–4.5 × 0.6–1.4 cm) that are densely imbricated (vs loosely arranged). Zingiber emeiense futher differs from Z. bambusifolium subsp. bambusifolium by its running rhizome with the vegetative rhizome units having a pseudo-neck that is 12–19 cm long (vs rhizome compact and pseudo-neck absent), longer ligules (7–9(–13) mm vs 1–6 mm), longer petioles (3–40 mm vs 1–5 mm), labella and lateral staminodes being deep violet with white striae (vs cream) and the latter connating to the former at basal 1/5 to 1/2 (vs 2/3–4/5).