Wurfbainia parviflora Kaewsri, 2022

Kaewsri, W. & Sangvirotjanapat, S., 2022, SIX NEW SPECIES OF WURFBAINIA (ZINGIBERACEAE) FROM THAILAND, Edinburgh Journal of Botany 79 (369), pp. 1-23 : 16-19

5. Wurfbainia parviflora Kaewsri , sp. nov.

Similar to Wurfbainia micrantha (Ridl.) Škorničk. & A.D.Poulsen but differs in its blade size (11–21 × 2–4 cm vs 15–30 × 0.6–2 cm), blade pubescent on both sides (vs glabrous on both sides) and calyx tube apex bilobed (vs trilobed) ( Table 4 ).

– Type: Thailand, Kanchanaburi, Thong Pha Phum National Park , Headquarters , c. 800 m altitude, 25 v 2004, Kaewsri 022 (holotype BKF!; isotypes BK!, E!). Figures 10 , 11 .

Clump-forming herb, leafy shoot slender, 0.8–1 m tall. Leaf sheaths pale brown; ligule 0.5–1 mm long, apex bilobed, margin ciliate, fragile; blades 10–12, oblong-lanceolate, oblong or narrowly elliptic, 11–21 × 2–4 cm, base attenuate or obtuse, apex acute, caudate, 2–3 cm long, upper surface glabrate, with brown hair along midvein, lower surface densely subtomentose, sessile. Inflorescence lax, arising from rhizome, obovoid or conical, c.(4.8–)5 × (2.6–) 3 cm; peduncle c. 2.5 cm long; peduncular bracts deltoid, apex acute, margin hairy, brown, subleathery; fertile bracts lanceolate, c.1.5 × 0.6 cm, apex acute, margin ciliate, reddish brown, outer surface with sparse hair, papery; bracteoles tubular, c. 1 cm long including ovary, apex acute and shallowly split on one side, outer surface sparsely pubescent. Flower c. 2.9 cm long, yellowish white; ovary subellipsoid, c. 2 mm long, pubescent; style c. 3.2 cm long, including ovary; stigma cup-shaped, ostiole narrowly transverse, glabrous; epigynous glands c. 2 mm long; calyx c. 1.5–2.1 cm long including ovary, apex bilobed and shallowly split on one side, outer surface sparsely pubescent; floral tube equal to calyx, pinkish white, sparsely pubescent; dorsal corolla lobe oblong, c.1 × 0.3 cm long, apex acute; lateral corolla lobes oblong, c.1 × 0.2 cm long, apex acute; lateral staminodes minute, tooth-like, c. 1 mm, creamy white with red spots at base; labellum narrowly hooded, obovoid, c.1.5 × 0.9 cm, base attenuate, apex bilobed, margin wrinkled and revolute, yellow with white blotch from base along median band almost to apex, with scattered crimson dots inside the median blotch and many transverse crimson stripes on each side; stamen: filament ribbon-like, c. 5 mm long; anthers c.5 × 2 mm, dehiscing lengthwise; anther crest trilobed, c.3 × 2 mm, pale yellow, central lobe largest, apex rounded and emarginate, slightly reflexed, lateral lobes auriculate, apex rounded. Fruit subglobose, c. 1.2–1.5 cm in diameter, 2–4 per infructescence, densely covered with fine spines, pinkish red; seeds c. 5 mm in diameter, angular, arillate.

Phenology. Flowering and fruiting between April and August.

Distribution. Known only from the type locality (see Figure 3 ).

Habitat. Dry evergreen forest in light gaps at c. 800 m altitude.

Etymology. The specific epithet refers to the small flower.

Proposed IUCN conservation category. Least Concern (LC). This species is found only in Thong Pha Phum National Park, Kanchanaburi Province. According to field observations, there are about five subpopulations in the wild. None of these populations are under threat, and they all grow in a well-protected area. Wurfbainia parviflora is therefore assessed as Least Concern.

Figures

Figure 3. Species distribution map. The unbroken-line box indicates the localities of Wurfbainia ellipticarpa, W. globosa and W. longiflora. The dashed-line box indicates the localities of Wurfbainia geostachyoides, W. parviflora and W. yingyongii.

Figure 10. Wurfbainia parviflora Kaewsri. A, Habit; B, bract; C, bracteole; D, calyx; E, corolla (dissected); F, stigma; G, stamen; H, labellum; I, infructescence; J, fruit (longitudinal section); K, seed. Drawn from Kaewsri 022 by W. Kaewsri.

Figure 11. Wurfbainia parviflora Kaewsri, sp. nov. A, Inflorescence; B, flower; C, infructescence. All photographs of the type collection (Kaewsri 022), taken by W. Kaewsri.