Globba chrysantha 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 : 140

Globba chrysantha Sangvir. & M.F.Newman , sp.nov. (Section Ceratanthera )

Similar to Globba bracteolata Wall. ex Baker in its yellow-orange flower, two linear anther appendages and globose ovary and fruits but differing by its erect inflorescence (vs. pendent inflorescence), and membranaceous, light green leaves (vs. thick, dark green leaves with red tint).

Type: THAILAND. Nakhon Nayok, Nang Rong Waterfall, 16 September 1972, Maxwell J. F. 72-368 (holotype BK!, isotype AAU!). Fig. 1 .

Lithophytic herb, 20–50 cm tall. Leaf sheaths c. 3 bladeless, pubescent; ligule shallowly bilobed or truncate, 2–4 mm long, glabrous or puberulent; blades 6–9, elliptic, 8.5–21 × 2.5–4.5 cm, base obtuse, apex caudate, membranaceous, pubescent below, strigillose along veins above, light green; petiole short, 1–2 mm long. Inflorescence erect, lax, conical, 4 × 3.5 cm; peduncle 1–2 cm long; bracts and bracteoles caducous orange, elliptic, c. 5 × 3 mm, apex acute, glabrous; cincinni lax, 1–2 cm, to 5 flowers on each, orange. Flowers 2.6 cm long; ovary globose, 2–3 mm long, yellow-orange; style filiform; stigma geniculate, ostiole ciliate; calyx infundibuliform, c. 6 mm long, apex trilobed with acute apices; floral tube 11 mm beyond calyx, hairy, yellow-orange; dorsal corolla lobe strongly hooded, elliptic, 5 × 1 mm, apex obtuse, yellow-orange; lateral corolla lobes shallowly hooded, elliptic, 5 × 1 mm, apex obtuse, yellow-orange; lateral staminodes oblong, c. 7 × 2 mm, slightly longer than lateral corolla lobes, curved, apex acute, yellow-orange; labellum oblong, 10 × 2 mm, base obtuse, apex shallowly bilobed, rounded, nectar tube c. 4 mm long, yellow-orange with red spot of varying intensity; stamen: filament c. 18 mm long, yellow-orange; anther elliptic, c. 2 × 1 mm; connective tissue and appendages semi-transparent orange, appendages 2; ⚥ flower: linear, c. 3 × 1 mm, held at c. 90° to anther, apex acute; ♂ flower: linear, curved, c. 3 × 1 mm, apex acute. Fruit orange, globose, c. 5 mm in diam., verrucose; seeds brown, ovoid, 2 × 1 mm; aril white. Bulbils corky, ovoid, 3–10 × 3–5 mm, protruding from leaf sheaths.

Etymology: Greek, chryseos, golden and anthos, flower.

Distribution: Endemic to Thailand.

IUCN assessment proposed: Least Concern (LC). Globba chrysantha was collected in Nakhon Nayok and Prachinburi, in the protected areas of Nang Rong Waterfall and Khao Yai National Park. About 250 mature individuals were seen in Prachinburi, scattered and growing in sandstone bedrock along a stream. As there is no specific threat to this species, it is assessed as of Least Concern.

Ecology: Growing in cracks in sandstone along shady streams.

Specimen examined: THAILAND. Nakhon Nayok: Nang Rong Waterfall, 100 m, 4 August 1992, Larsen et al. 43757 ( AAU); ibid., 1 September 2017, Pooma et al. 8053 ( E); Pha Tabak Waterfall, 28 June 2001, Maxwell J. F . 01- 333 (A, CMU, L). Prachinburi: Khao Yai National Park , 5 September 2015, Sangvirotjanapat 771 ( BKF, QBG) .

Notes: Globba chrysantha is recognised by its upright inflorescence with yellow-orange flowers. Two flower morphs occur in the inflorescences and the anthers have two appendages. Using these two characters alone, G. chrysantha could be placed either in section Ceratanthera or section Nudae subsection Mediocalcaratae . The fact that the two flower morphs are randomly placed in the inflorescence and that the fruit is globose indicates that G. chrysantha belongs to section Ceratanthera ( Table 1).

Figures

FIGURE 1. Globba chrysantha Sangvir. & M.F.Newman (Sangvirotjanapat 771) A. Habitat B. Inflorescence C. Habit D. Hermaphrodite flower (left) and functionally male flower (right) E. Flower dissection; lcl = lateral corolla lobe, dcl = dorsal corolla lobe, ls = lateral staminode, lb = labellum, at = anther thecae, hermaphrodite flower (left) and functionally male flower (right) F. Fruit on cincinnus (left) and bulbil (inset). Scale bars: C = 10 cm; D & F = 1 cm. Photographs by S. Sangvirotjanapat.