Curcuma glandulosa P. P. Thwe, M. M. Aung & Nob. Tanaka, 2025

Thwe, Phyo Phyo, Aung, Mu Mu & Tanaka, Nobuyuki, 2025, A new species of Zingiberaceae, Curcuma glandulosa (Subgenus Ecomatae), from Myanmar, PhytoKeys 266, pp. 311-316 : 311-316

Curcuma glandulosa P. P. Thwe, M. M. Aung & Nob. Tanaka sp. nov.

Fig. 1

Type.

Myanmar • Shan State: Taunggyi Bird Sanctuary, Taunggyi Township, Taunggyi District , 20°46'10"N, 97°03'22"E, 1660 m elev., 23 June 2023, Nobuyuki Tanaka, Mu Mu Aung, Phyo Phyo Thwe MY 6745 (holotype-TNS; isotype-RAF) .

Diagnosis.

Curcuma glandulosa is similar to C. sahuynhensis ; however, it is distinguished from it by a combination of the following characters: red leafy stems (vs. green), broadly lanceolate lamina developing after flowering (vs. ovate to elliptic and developing at the same time of flowering), white bracts with red stripes (vs. whitish to pale green at base with coral pink to red tinge), white anther (vs. yellow), and having prominent anther crest (vs. almost negligible).

Description.

Small rhizomatous herb, ca. 40 cm tall. Rhizome not thickened, bearing tubers; tubers ovoid, externally whitish brown, internally cream white. Leafy shoot emerged after or at the same time of blooming, leafy stem red; pseudostem with leaf sheath, red; sheathing bracts 1–4; petiole slender, ca. 25 cm long; leaf blade broadly lanceolate, ca. 20 cm long, ca 8 cm wide at early stage of development, base obtuse, entire along the margin, acute at the tip, glabrous on both surfaces, light green. Inflorescence lateral, arising directly from rhizomes before leaves develop, with 1–3 sheathing bracts; peduncle stout, 10–12 cm long, sheathing bracts reddish white, glabrous; spike 4–7 cm long, 3–5 cm diam; bracts 3–8 per inflorescence, 4.5–5.5 cm long, ca. 3 cm wide, broadly ovate, round or acute at the apex, white with numerous red stripes, puberulous towards the apex and on the edges; bracteoles indistinct, translucent white, glabrous, one per flower. Flower 5–5.5 cm long, exserted from bracts, with 2–3 cincinnus flowers; calyx tubular, ca. 2 cm long, ca. 1 cm wide, apex 3 - toothed with unilateral incision, an incision 1–2 mm long, translucent, white, puberulous; floral tube white, expanded at apex, 3 cm long, puberulous; dorsal corolla lobe triangular-ovate, 2 cm long, 0.5 cm wide (the widest position), attenuate at the apex, slightly convex, white, slightly yellowish at apex, puberulous at apex edge, glabrous on both surfaces; lateral corolla lobes oblong, acute at apex, 1.5 cm long, 0.6 cm wide, glabrous, white; labellum 2–2.3 cm long, 1.7 cm wide, trullate to rhomboid, deeply incised at distal part, an incision ca. 1 cm, whitish yellow at base, lemon yellow at apex with bright yellow raised band running through the center, with two red lines along the band at base, sometimes red lines very weak, glabrous, margin puberulous; lateral staminodes ovate to rhomboid, 2 cm long, 0.9 cm wide, rounded at apex, glabrous, lemon yellow, lighter towards the base, base whitish; stamen 1.3–1.6 cm long; filament ca. 1 cm long, yellowish white, 0.3 cm wide at apex, 0.6 cm wide at base, with glandular hairs; anther curved, spurred, connective tissue white, glandular, spur L- shaped, anther spurs 3 mm long, parallel with acute apices, white; anther crest 1 mm long, curved backwards, deeply emarginate, yellowish white; thecae 5 mm long, dehiscing along entire length, pollen white; epigynous glands two, straight, ca. 5 mm long, ca. 0.5 mm in diameter, apex subulate, white, creamy-white at base; ovary sub-globose, 2–3 mm long, ca. 2 mm wide, trilocular, pubescent, white; style white, glabrous; stigma capitate, placed between anther spurs, ca. 0.8 mm long, 1 mm wide, light yellowish white; ostiole ciliate. Fruit and seeds not seen.

Etymology.

The specific epithet “ glandulosa ” refers to its character of densely glandular anther.

Distribution, habitat, and ecology.

Thus far known only from the type locality in Taunggyi, southern Shan State. However, it could be distributed in a wider range of limestone hills laying in eastern part of Myanmar. Growing in humid soil places at the edge of mix deciduous forests 1,500 –1,600 m elevation. Inflorescence is arising before leafy shoot emerged.

Phenology.

Flowering in early rainy season from the end of May to mid-June. Fruits are not seen, and fruiting period is unknown. But we estimate that the fruit probably ripens during the rainy season from July to August.

Note.

Curcuma glandulosa also resembles C. xanthella Škorničk. , described from Vietnam, but the new species is distinguished from it by having a sharply L-shaped anther (vs. gently L-shaped, crescent-shaped), a trullate to rhomboid labellum (vs. obovate), and shorter epigynous glands ( 5 mm vs. 15 mm).

Figures

Figure 1. Curcuma glandulosa P. P. Thwe, M. M. Aung & Nob. Tanaka. A. Habit; B. Side view of inflorescence with flowers; C. Rhizomes with tubers; D. Flowers with prominent red lines on labellum; E. Flowers without or with weak red lines on labellum; F. Side view of a flower; G. Flower parts (from above left): bract, dorsal and lateral corolla lobes, lateral staminodes; (from lower left) labellum with red lines, labellum with very weak red lines, side view of stamen, diagonally front view of stamen, epigynous glands with ovary. Scale bars: 5 cm (A); 3 cm (B); 2 cm (C – F); 1 cm (G).