Globba janae 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 : 142-145

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

Similar to Globba expansa Wall. ex Horan. ( Fig. 2A , Table 2) in its erect inflorescence with caducous bracts and four-appendaged flower but differing by its irregularly plicate leaf blades with undulate margins (vs flat leaf blades), globose, echinate fruit (vs ellipsoid with longitudinal ridges).

Type: LAO PDR, Viengchan Province, Vang Vieng, Bane Phou Din Deng , 18º57’42’’N 102º26’16’’ E, 338 m, 23 June 2012, Leong- Škorničková, Trần, Bouamanivong, Santhammavong, Souvannakhoummane JLS1769 (holotype SING! [0192239], isotypes E!, HNL, P! [ P00807164 ], PR!). Fig. 3 .

Lithophytic herb, 20–50 cm tall. Leaf sheaths 4–6, bladeless dark red; blades 6–7, elliptic, 6–18 × 4–8 cm, base obtuse, truncate, or cordate, apex acuminate, irregularly plicate, shiny dark green above, pubescent below, sparsely strigillose hairs along veins, margin undulate; petiole 1–2 cm long; ligule truncate or shallowly bilobed, 3–4 mm long, pubescent. Inflorescence erect, lax, secund, 6–10 × 4–5 cm; peduncle c. 1 cm long, green, puberulent; rachis green with red tint, puberulent; bracts elliptic, 3 × 0.3–1 cm, apex acute, green; bracteoles caducous, elliptic or ovate, 1.4–3 × 0.3–1 cm, apex mucronate, keeled, glabrous, yellowish orange; cincinni 1–2.5 cm long, flowers crowded at tip. Flowers 3.3–3.5 cm long, pale yellow with dark spot at labellum; ovary ellipsoid, c. 2 × 2 mm, blistered, yellowish green; style filiform; stigma cup-shaped, ostiole ciliate; calyx infundibuliform, 3–4 mm long, unequally trilobed with acute apices, blistered, yellow; floral tube c. 13 mm long, sparsely hairy, pale yellow; dorsal and lateral corolla lobes hooded, elliptic, 8–10 × 1–1.5 mm, apex obtuse, pale yellow; lateral staminodes elliptic, 14–18 × 5–12 mm, apex acute or obtuse, twice as long as lateral corolla lobes, pale yellow; labellum triangular, c. 11 × 9 mm, bilobed, pale yellow with dark orange or brown spot at centre, base truncate, apex acute, nectar tube c. 5 mm long. Stamen: filament c. 23 mm long, pale yellow; anther elliptic, c. 2 × 1 mm, connective tissue orange, appendages 4, upper pair bigger, triangular, lower pair about half length of upper pair, c. 3 × 1 mm, base broad, apex acuminate, curved, orange. Fruit globose, c. 10 mm in diameter, echinate, green. Bulbils not seen.

Etymology: The epithet ‘ janae ’ honours Dr. Jana Leong-Škorničková , who has generously contributed to our revision of Globba . This species was first discovered by her during field work in 2012 with a team from the Herbier National du Laos (HNL).

Distribution: Endemic to Lao PDR.

Proposed IUCN conservation status: Data Deficient (DD). Only two subpopulations have been seen, one from a small area of limestone cliffs above the Nam Song on the outskirts of Vang Vieng town, and the other a few kilometres south of Vang Vieng. The number of individuals would be 30–50. Further exploration of limestone cliffs in this area may reveal more populations.

Ecology: Growing on limestone bedrock in partial shade.

Specimen examined: Lao PDR, Viengchan Province, Vang Vieng, Bane Na Khoun , 278 m, 24 June 2012, Leong- Škorničková et al. 1804 ( E, HNL, P, PR, SING); ibid., 15 June 2019. Insisiengmay OI-337 ( E, P, HNL) .

Notes: This species is easily recognised by its leaf blades which are broad and undulate with truncate or cordate bases. Moreover, the blistered calyx and echinate fruit are good characteristics for identification. Spiny fruits are known in G. dasycarpa , in which the spines are acute and G. janae , in which they are obtuse.

Figures

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

FIGURE 3. Globba janae Sangvir. & M.F.Newman (Leong-Škorničková et al. 1804 (A, B, G) and O. Insisiengmay et al. OI-337 (C–F)) A–B. Habitat C. Inflorescence D. Flower, front view E. Bract F. Bracteoles G. Tip of cincinnus H. Flower I. Ovary and calyx J. Fruit. Scale bars: C–H. & J = 1 cm; I = 5 mm. Photographs A, B & G by Jana Leong-Škorničková; C–F & H–J by S. Sangvirotjanapat.