Curcuma sahuynhensis

Curcuma sahuynhensis Škorničk. & N.S.Lý, Phytotaxa 192(3): 185 (2015).

Curcuma sahuynhensis Škorničk. & N.S.Lý, Photo by Hoang Thanh Son

its native range is Vietnam.

Vietnamese name: 

Nghệ Sa huỳnh

Latin Name: 

Curcuma sahuynhensis Škorničk. & N.S.Lý

Synonym Name: 

No

Etymology:

The specific epithet sahuynhensis is derived from Sa Huỳnh town, hometown of the second author, where this species was first collected. Sa Huỳnh area is well-known for its ancient rich culture dating to 1000 BC to 200 AD.

Family: 

Zingiberaceae

Description: 

Small rhizomatous  herb to 0.8 m  tall. Rhizome ovoid to narrowly ovoid, 1.5–4.0 × 0.5–1.0 cm, occasionally with a thin branch pointing downwards, light brown externally, creamy white to pale yellow internally, slightly aromatic, root tubers fusiform, 2–6 × 0.8–1.8 cm, light brown externally, pure white internally, buried deeply in the ground (distanced 8–15 cm from the main rhizome). Leafy shoots with ca 1–2 leaves at the time of flowering, with up to 10 leaves on mature plants past flowering; pseudostems 10–15(–20) cm long, green, composed of sheathing bracts and leaf sheaths; sheathing bracts 3–5, green, glabrous or sparsely  puberulent,  turning  dry  and  papery  with  age;  leaf  sheaths  green, glabrous; ligule up to 5 mm long, bilobed, hyaline, greenish white, translucent, glabrous, margin sparsely hairy; petiole 2–20(–24)  cm  long (petiole  of  first leaf shortest,  innermost leaves longest),  canaliculate, green, glabrous;  lamina slightly unequal,  ovate to  elliptic, 20–38  ×  9–16(–18) cm (measured  in  mature plants in  late  stage of flowering), plicate, adaxially  bright green, glabrous, abaxially lighter green, glabrous but sparsely puberulous along midrib and near margin in apical part of lamina; midrib green, glabrous above, very sparsely puberulous below (hairs restricted to sides  of midrib); base obtuse to rounded, slightly oblique;  apex attenuate to  acuminate, puberulent. Inflorescence lateral, arising at the same time as first 1–2 leaves; peduncle 6–16 cm long, to 8 mm in diameter, light green in parts exposed to  light, sheathed by  3–5 leafless, light  green, glabrous sheaths  (turning dry and  papery with age);  spike to 6–15 cm long,  5–9 cm in diam. at the middle,  with no obvious coma, composed of 10–23 bracts; bracts 3.0–5.5 × 1.5–4.0 cm, broadly to narrowly ovate to rhombic (broader at base, narrower at the apex), whitish to pale green at base with various degree of coral pink or red tinge, both sides glabrous, connate in lower 1/3–1/4, apices acute to narrowly acute, reflexed; cincinni with 3–5 flowers at the base of the inflorescence, 1–2 flower at the top; bracteoles subulate, 1–5 mm long, semi-translucent white, glabrous, often fully reduced. Flowers 3.5–5.5 cm long, exserted from bracts; calyx 14–19 mm long, 3-toothed, with unilateral incision, 5–8 mm, glabrous, semi-translucent white or with pink tinge; floral tube 1.8–2.8 cm long, narrowly cylindrical at base for ca 1.3–1.8 cm above the ovary, funnel-shaped at apex, externally white or with pink tinge, externally puberulous (less so in basal part), internally white, turning pale yellow towards apical part, densely hirsute at apical part, sparsely hirsute towards the base, with dorsally placed loose groove holding the style; dorsal corolla lobe 15–22 × 6–11 mm, triangularly ovate, concave, white or pale yellow with various degree of pink  or  red  tinge,  glabrous,  apex  mucronate,  mucro ca 1 mm,  sparsely  puberulous;  lateral  corolla lobes 15–20 × 6–9 mm, triangular, apex broadly acute to obtuse, slightly concave, white or pale yellow with various degree of pink or red tinge, glabrous; labellum 15–23 × 12–18 mm, slightly obovate, with an incision 2–7 mm long, cream white at base, warm rich yellow at apex with bright yellow-orange band running through the centre; lateral staminodes 15–22 × 10–14 mm, unequally ovate to obovate to rhomboid, warm rich yellow, lighter towards base, covered with short glandular hair adaxially. Stamen 11–12 mm long; filament 4–5 mm long, cream-white to pale yellow, 3–4 mm broad at base, 2.0–2.5 mm broad at apex (the point of attachment to the connective), densely puberulent (glandular hair); anther  L-shaped (angle ca 110°–120°), spurred, connective tissue pale yellow to pale yellow-orange, densely puberulent (glandular hair), anther spurs 3.5–5.0 mm long, stout, parallel with acute apices slightly divergent, creamy white to pale yellow, anther crest 0.3–1.0 mm long (almost negligible in some plants), apex emarginate, pale yellow; anther hecae 6–7 mm long, dehiscing along entire length, pollen white. Epigynous glands two, creamy yellow, 4–6 mm long, ca 0.6 mm in diameter, with blunt apices. Style white, glabrous; stigma capitate, ca 1 mm wide, creamy white; ostiole shortly ciliate facing forward. Ovary 3–5 × 2–4 mm, trilocular, creamy white, usually glabrous (rarely sparsely hairy at apical part). Fruit a globular trilocular capsule (with locules visibly bulging in ripe fruit), 11–15 mm in diameter, white, glabrous; seeds irregularly obovoid, 4–5 × 2–3 mm, light brown, shiny, enclosed in translucent white, laciniate aril.

Flowers: 

Flowers  from August  to October  and  fruits  from September to  November

Distribution: 

Vietnam (Quảng Ngãi).

Ecological: 

Growing in coastal lowland forests, on gravelly infertile soil in open spaces, shrubby vegetation as  well as  Acacia  plantations.  Curcuma sahuynhensis  flowers  from August  to October  and  fruits  from September to  November.  This flowering  pattern corresponds  with the  beginning  of the rainy  season in  central to northern Vietnam.

Chemical constituents and Pharmacology:

Uses:

The  species is locally  called  Rau  Nghệ [Rau =  vegetable, Nghệ =  Turmeric (Curcuma)]. The name reflects the fact that C.  sahuynhensis  is often harvested as a local vegetable. Inflorescences and young leafy shoots are sold in the local market when in season and are used for preparation of boiled vegetable or soup (usually mixed with another wild vegetable: Lá Giang - Aganonerion polymorphum Pierre ex Spire (1905: 43), Apocynaceae).

Typus:

Collector Team:

Lý Ngọc Sâm & Phan Thế Cường Lý-486

Locality:

Quảng Ngãi Province: Đức Phổ Dist., Phổ Thạnh commune, Đồng Vân Village, Núi Đồng Đế, Núi Đồng Vân, 183 m

Collection Date:

4 Sep 2010

Type Herbaria:

holotype SING

isotype E

isotype P

isotype VNM

Latitude:

14° 39' 28"

Longitude

109° 2' 22" E

Distribution Of Types:

Vietnam (Indo-China, Asia-Tropical)

References

Leong-Skornickova, Jana & Ly, Ngoc-Sam & Binh, Nguyen. (2015). Curcuma arida and C. sahuynhensis, two new species from subgenus Ecomata (Zingiberaceae) from Vietnam. Phytotaxa. 192. 181-189. 10.11646/phytotaxa.192.3.4.