Globba rupestris Sangvir. & M.F.Newman, 2021

Sangvirotjanapat, Sunisa & Newman, M. F., 2021, Eight new species of Globba (Zingiberaceae) from Thailand and Lao PDR, Phytotaxa 505 (2), pp. 139-156 : 155

Globba rupestris Sangvir. & M.F.Newman , sp. nov. (Subgenus Globba )

Similar to Globba nisbetiana Craib ( Fig. 2C ) in its small inflorescence (c. 2 × 2.5 cm), flowers arranged distichously on the cincinni, with four-appendaged anthers but differing by its long peduncle 3–7.5 cm long (vs. 1.5–2 cm long), yellowish orange bracteoles (vs. green bracteoles), and oblong lateral staminodes, c. 7 × 2 mm (vs. elliptic c. 9 × 4 mm).

Type: LAO PDR. Oudomxay, 5 km S of Oudomxay town, 860 m, 17 June 2012, Jana Leong-Škorničková, Tran Huu Dang, Ota Sida, Kittisak Phoutthavong, Somdy Oudomsack JSL 1734 (holotype SING! [ SING0201160 ], isotypes E!, HNL, P [ P00807169 ], PR, QBG!). Fig. 9 .

Lithophytic herb, 19–60 cm tall. Bladeless leaf sheaths 4–5, minutely hairy; ligule truncate or shallowly bilobed, c. 3 mm long, hairs sparse; blades 6–7, elliptic, 1.5–15.5 × 1.3–4.5 cm, base obtuse, apex acuminate, plicate, with purple tint below, shiny dark green above, sparsely strigillose along veins; petiole to 5 mm long, glabrous. Inflorescence pendent, c. 2 × 2.5 cm; peduncle 3–7.5 cm long, green or maroon, pubescent; rachis green, puberulent; bracts and bracteoles caducous, elliptic, 5–6 × 3–4 mm, keeled, glabrous, yellowish orange, apex mucronate; cincinni to 5 mm long, flowers distichous, crowded at tip. Flowers 3–3.2 cm long, orange; ovary ellipsoid, c. 3 × 1.5 mm, white to pale yellow; style filiform; stigma cup-shaped, ostiole ciliate; calyx infundibuliform, 3–4 mm long, yellowish orange, unequally trilobed with acute apices; floral tube c. 12 mm long, hairy; dorsal and lateral corolla lobes hooded, elliptic, 3–6 × 1.5–2.5 mm, apex obtuse; lateral staminodes oblong, c. 7 × 2 mm, apex acute, as long as lateral corolla lobes; labellum triangular, 5–6.5 × 4–6.5 mm, bilobed, orange with dark orange or red spot at centre, base truncate, apex acute, nectar tube c. 8 mm long; stamen: filament c. 23 mm long; anther elliptic, c. 1.5 × 1 mm, connective tissue orange, appendages bifid about half their length, upper pair bigger, triangular, c. 3 × 1 mm, base covering whole side of anther, apex acuminate, curved. Fruit globose, c. 5 mm in diam., verrucose, green. Bulbils produced on peduncle or within leaf sheaths, ovoid, 3–5 × 2–3 mm, corky.

Etymology: Latin, rupestris , growing in rocky places.

Distribution: LAO PDR and Thailand.

Proposed IUCN conservation status: Near Threatened (NT). Globba rupestris has an extent of occurrence (EOO) of about 12,000 km 2 and an area of occupancy (AOO) of 24 km 2. It is known to occur in four localities, three of them in protected areas. There is no major threat but the subpopulations may be disturbed by tourist activities. As it is a lithophyte with its roots embedded in cracks in rocks, the population size will not be much changed if the habitat has no threats. This species is therefore assessed as Near Threatened.

Ecology: Growing in shade with high humidity along streams or by waterfalls.

Specimens examined: Lao PDR: Louangphabang: Muang District, Ban Pha Yuak , 773 m, 17 July 2014, Maknoi et al. L3-028 ( HNL, QBG); ibid., Ban Pha Yuak, 890 m, 18 July 2014, Maknoi et al. L3-071 ( HNL, QBG) .

Thailand: Nan: Pua, Tham Pha Kong, Doi Phu Kha National Park , 800 m, 26 June 2002, Srisanga 2540 ( QBG) . Phayao: Chiang Kham District, Doi Pha Dam, Rom Yen subdistrict, 956 m, 15 August 2013, La-ongsri et al. 3032 ( QBG) ; Chiang Kham district, Doi Pha Dam , 469 m, 25 June 2014, La-ongsri et al. 3446 ( QBG) .

Notes: Globba rupestris is distinct by its pendent inflorescence with long peduncle. The cincinni are crowded at the tip of the inflorescence.

Figures

FIGURE 2. A. Globba expansa Wall. ex Horan. B. G. leucantha Miq. C. G. nisbetiana Craib. Photographs by S. Sangvirotjanapat.

FIGURE 9. Globba rupestris Sangvir. & M.F.Newman (Leong-Škorničková et al. 1734) A. Habitat B. Habit C. Inflorescence D. Flower, side view E. Flower, front view F. Filament and anther G. Lateral staminodes H. Dorsal corolla lobe I. Lateral corolla lobes J. Labellum K. Anther and anther appendages Scale bars: B = 10 cm; D–G = 1 cm; K = 5 mm. Photographs by Jana Leong-Škorničková.