Curcuma globulifera Škorničk. & Soonthornk., 2021

4. Curcuma globulifera Škorničk. & Soonthornk. View in CoL , sp. nov. (subg. Curcuma ) — Fig. 4 View Fig

Similar to C. strobilifera Wall. ex Baker in its dense globular to elliptic inflorescences on short peduncle composed of green bracts and yellow flowers, but differs in prominently branched rhizome structure, lateral inflorescences which appear just before the leaves, flowers with pale yellow staminodes and pale yellow labellum with darker median band (vs rhizome consisting of series of a few unbranched globular rhizomes, inflorescences central and flowers with uniformly warm yellow labellum and lateral staminodes in C. strobilifera ). — Type: Sutthinut Soonthornkalump Sutt-213 (holo BKF, including flowers preserved in spirit as part of a single specimen; iso QBG, SING,both including flowers preserved in spirit as part of a single specimen), Thailand, Tak Province, Mae Ramat District, Sam Muen Subdistrict , c. 500 m elevation, 4 May 2020, flowering .

Etymology. The specific epithet is derived from Latin globuliferus = bearing small globes, globular, and refers to the almost globular shape of the inflorescences, which appear on the ground just before the leaves.

Perennial rhizomatous herb, 25–50(–60) cm tall. Rhizome branched, main rhizome globose to ovoid, 3.5–4 by 4–5 cm, lateral branches of first order horizontal, 3–6 by 1–1.7 cm, second order branches perpendicular or diagonal to lateral branches, 2–3.5 by c. 1 cm, externally pale brown, covered with rusty coloured and decayed scales, internally pale to straw yellow, aromatic with pungent smell, taste bitter; root tubers ovate to fusiform, 2.3–4 by 1.6–2.3 cm, externally light brown, internally white. Leafy shoot with up to 5 leaves, appearing shortly after inflorescence; pseudostem 15–35 cm long, composed of 2 leafless sheaths and 2 or 3 leaf sheaths, outer leafless sheath green with brownish tinge, puberulent, margin hyaline; ligule 1.5–2 mm long, bilobed, hyaline, greenish white, semi-translucent, glabrous except for a few stipitate hairs c. 0.1 mm long on upper margin; petiole 20–45(–60) cm long, canaliculate, green, adaxially glabrous (groove), abaxially puberulent; lamina elliptic to slightly obovate, 20–48 by 7–12.5 cm, plicate, adaxially mid to dark green, often with a narrow or broad red patch along midrib that may or may not show through to the underside, running almost entire length of lamina, abaxially somewhat paler, glabrous on both sides, midrib green with slight red tinge adaxially (plain green on plants without red patch), green with sparse hairs (c. 0.5 mm long) abaxially, margin hyaline, semi-translucent white, c. 0.1 mm wide, base obtuse to slightly oblique, apex acuminate to narrowly acuminate. Inflorescence lateral, emerging before leafy shoots; peduncle basally embedded in ground, usually with 2 leafless sheaths, cream-white basally, light green with reddish to brown tinge, puberulent, margin hyaline; thyrse c. 5–9 by 5–7 cm, composed of 14–30(–40) fertile bracts, coma bracts absent; bracts broadly obovate to ovate, 3.8–5.5 by 3.5–6 cm, connate in basal 1/3–1/2, bright green to brownish green with pale green venation, adaxially puberulent, abaxially glabrous, apex broadly acute to obtuse, strongly reflexed, margin hyaline, finely hairy (c. 0.1 mm long); cincinni with up to 3 or 4 flowers at basal bracts (2 or 3 lowermost bracts without flowers), the number gradually decreasing upwards, flowers in uppermost bracts often underdeveloped or aborted and covered by developed bracteoles; bracteoles broadly ovate to triangular, 7.5–11 by 9–14 mm wide at base (outer ones largest), hyaline, semi-translucent white at base with green tinge distally, apex broadly acute, slightly concave, glabrous. Flowers c. 5 cm long, exsert- ed from bracts; calyx 6.5–7 mm long, tridentate, with unilateral incision 1.5–2 mm long, teeth c. 0.5–0.7 mm long with blunt apex, semi-translucent white with green tinge distally, glabrous; floral tube 3–3.5 cm long, narrowly cylindrical at base, widening distally, externally white to cream-white, glabrous, internally white and glabrous in basal 1/2, distally cream-white with bright yellow patch on ventral side, puberulous; dorsal corolla lobe broadly ovate to triangular, 10–11 by 9.5–10 mm wide at base, semi-translucent cream-white to pale yellow, glabrous, apex hooded and mucronate, mucro c. 1 mm long, margin hyaline; lateral corolla lobes triangular with obtuse concave apex, 9.1–10 by 7.1–7.5 mm wide at base, semi-translucent cream-white to pale yellow, glabrous, margin hyaline; labellum broadly ovate to irregularly orbicular, 13–15 by 13–16 mm, obscurely trilobed, side lobes folding upwards, midlobe straight with an incision c. 1 mm long, labellum cream-white to pale yellow with bright yellow median band extending from base of labellum to margin, glabrous throughout except for some hair at base; lateral staminodes irregularly broadly oblong, 10.5–11 by 7–8 mm, apex obtuse, folded inwards at centre of apex, cream-white to pale yellow, adaxially with glandular hair, abaxially glabrous; Stamen c. 7 mm long; filament 5.5–6 mm long, 4–5 mm broad at base, c. 1.5 mm broad at point of attachment, cream-white to very pale yellow, abaxially hairy with glandular hairs; anther spurred, ovate, 5.5–6 mm long (including spurs), c. 2.5–3 mm wide at base, connective tissue cream-white to very pale yellow, with glandular hairs on sides and abaxially, anther spurs narrowly triangular, c. 2 mm long, apex sharp, slightly curved downward, anther crest absent; anther thecae c. 3 mm long, dehiscing along entire length, white, glabrous, pollen white; epigynous glands 2, cylindrical, with irregularly blunt apex, 2–2.5 mm long, c. 0.7 mm diam, yellow; style white, glabrous; stigma capitate, c. 1 by 0.5 mm, white; ostiole smooth, sparsely ciliate, facing forward; ovary ovoid, 2.5–2.6 by 1.5–1.9 mm, trilocular, white to cream, placentation axile, pubescent. Fruit and seeds not seen.

Distribution — Known only from Tak and Kanchanaburi Provinces.

Habitat & Ecology — Bamboo and deciduous dipterocarp forest at 400–800 m elevation. Flowering starts in the rainy season and lasts from May to August. The plants enter dormancy in December. Flowers open in the morning and last a single day.

Conservation status — Only the population from Tak Province is supported by herbarium material, while evidence for the distribution of this species in Kanchanaburi Province (Thong Pha Phum and Sangkhla Buri Districts) is derived from photographs. We obtained this species from a local market. Although the precise location of this species and information on population sizes remain unknown, locations in both provinces are in proximity of National Parks and the species evidently sets seed. Judging by the photographs, it forms large populations. Although we propose the status as Data Deficient, we feel that this species is in least danger of the four described in this paper.

Vernacular names and Uses — Salika lin thong ( สาลิกาลิน ทอง) = golden-tongued myna. The plant is sold as an ornamental in local markets, and is used locally in spiritual practices, where dried rhizome and inflorescences are an ingredient in the preparation of an amulet to attract attention and popularity.

Other specimen examined. THAILAND, Tak Province, Mae Ramat District, Sam Muen Subdistrict , c. 500 m elevation, 14 May 2020,flowering, Sutthinut Soonthornkalump Sutt-215 ( BKF, including flowers preserved in spirit as part of a single specimen) .