Curcuma sumatrana Miq. — Plate, 1861

Curcuma sumatrana Miq. — Plate View in CoL 1

Curcuma sumatrana Miq. (1861) 615. — Type: Diepenhorst [1327 H.B.] (lecto, designated here, Acc. No. BO 0083511 ), Indonesia, Sumatra Occ. In Priaman .

Terrestrial herb, to 135 cm tall. Rhizome ovoid, up to 3 cm long and 2 cm wide, with a single branch, which turns into another main rhizome parallel to the previous one, externally cream white with pink tinge, internally light purple with cream borders and a purple line in between outer and inner part, aromatic. Root tubers not seen. Leafy shoot usually with 2 leaves, base c. 2.5 cm diam, pinkish white, pseudostem 3 – 50 cm long, with 2– 4 sheathing bracts, 25– 34 cm long, pinkish white near base, reddish brown above, pubescent; ligule 3 mm long, deeply bilobed, reddish brown, densely hairy; petiole 29–36 cm long, reddish brown near base, green towards the lamina, winged, shortly hairy; lamina 57–64 by 24– 30 cm, elliptic, plicate (clearly seen as hard veins in dry specimens), adaxially dark green, glabrous with hairs along side of the main veins, abaxially pale green with a maroon tinge towards the margin, glabrous, base acute, apex caudate, midrib green. Inflorescence terminal, appearing centrally from the middle of leafy shoot, 20–40 cm long. Peduncle 4–18 cm long, erect, white with reddish tinge. Spike 14– 25 by 5.5–7 cm, cylindrical, consisting of 15– 29 bracts. Coma inconspicuous, uppermost 4 – 5 sterile bracts are similar in colour and shape to fertile bracts, uppermost 2 – 3 bracts are smaller and lighter in colour. Fertile bracts ovate-elliptic with rounded apex, c. 6 – 6.5 by 5 – 6.5 cm, bright red, gradually becoming yellowish cream at base, connate in the lower half, shortly hairy on both sides. Cincinni with 3 – 5 flowers. Bracteoles one per flower, c. 13 mm long, translucent white. Flowers c. 6.5 cm long. Calyx c. 13 mm long, translucent white, obscurely 3-toothed, unilaterally split 4 mm from apex. Floral tube 4.1–4.4 cm long, white, glabrous; dorsal corolla lobe c. 18 by 9 mm, translucent white, triangularly ovate, concave, mucronate, mucro 2 – 3 mm long, glabrous, lateral corolla lobes c. 17 by 7 mm, translucent white, triangular with rounded, slightly concave apex, glabrous. Labellum 1.5 by 1.7 cm, slightly emarginate, incision to 2 mm, light yellow with dark yellow median band. Lateral staminodes c. 11 by 5 mm, light yellow, glabrous. Anther versatile 8 by 3 mm, yellowish white; filament 3 mm long, 5.5 mm broad at base, 2 mm broad at upper part; anther thecae c. 6 mm long, whitish, dehiscing longitudinally the entire length of theca, anther spurs 3 mm long, anther crest absent. Ovary trilocular, 2.5 – 3 by 2.5 mm, white, hairy in upper part. Epigynous glands 2, 2 –3 mm long, cream, glabrous. Style 5 cm long, white, stigma white, ostiole not cilliate. Infructescence 1 fruit per bract, fruit a dehiscent capsule, ovoid, c. 2 by 1.1 cm, white with red tinge. Seeds elliptic, 6 by 5 mm, dark brown, aril translucent white, laciniate.

Distribution & Ecology — Endemic to West Sumatra, known only from Maninjau, Sianok, Lembah Anai, Kayu Tanam, and Ulu Gadut from the Barisan Range. No data on habitat preference are available for the early collections, but recent collections originate from secondary forests at elevations between 100– 500 m, often with many Laportea sp. (Urticaeae). This raises a question whether C. sumatrana is native to Sumatra. Unlike numerous vegetatively reproducing polyploid Curcuma species, which may be found naturalized all over Asia, the majority of seed-setting species from the subg. Curcuma are rather restricted in their distribution. They may colonize secondary habitats, but will not naturalize easily out of their natural range. Curcuma sumatrana is a seed-setting species (formation of fruits observed) and in spite of our extensive revision of Curcuma herbarium material (Leong-Škornicˇ ková et al. 2010) the species has not been found outside West Sumatra. We therefore believe that this species is native to Sumatra.

Phenology — Flowering May to September; fruiting observed from July onwards.

Vernacular name — Koenih Bimbo; Kamuniang (Maninjau).

Uses — Leaves are used for wrapping the flesh of durian fruit, which is then fermented to make a cooking ingredient called Pekasam. The water from boiled leaves is used to cure skin problems (itchiness).

IUCN assessment — The area of distribution of C. sumatrana is about 1 600 km 2 and consists of less than 10 localities, mainly in the Barisan Mountain range (between Maninjau Lake and Ulu Gadut). Based on the IUCN Red List criteria ( IUCN 2001), we propose a conservation status of Vulnerable (VU B1ab(iii)). However, as the habitat of C. sumatrana is affected by human activities and is in decline, the taxon is likely to qualify in the near future for the Endangered category.

Specimens examined. INDONESIA, West Sumatra, Kabupaten Agam, Kecamatan Tanjung Raya, Kanagarian Koto Malintang, Maninjau, Labuah Baru (0°18.144'S, 100°07.918'E), 1210 ft, 8 July 2009, flowering and fruiting, M. Ardiyani, Ari Anggara & Pitra Akhriadi 189 ( ANDA, BO, E) GoogleMaps ; Western Maninjau, Muko-muko, small hill behind Field Research Station of Andalas University , 500 m, 11 Sept. 1984, M. Hotta & T. Kohyama 356 ( ANDA) ; Maninjau, about 60 km west from Bukittinggi, Muko-muko, Gunung Datar, 12 May 1984, Asmiati 73 ( BO) ; ibidem, s.d., Roma Yuliet s.n. (ANDA); ibidem, 240–340 m, s.d., Reno Budi 110 ( ANDA) ; Bukittinggi, Siniok, 21 Oct. 1989, Laivia Syarana 027 ( ANDA) ; Kabupaten Pariaman, Sipisang Kayu Tanam, about 55 km north from Padang city, 150–450 m, 25 May 1995, Nofrida 64 ( ANDA) ; ibidem, 26 May 1995, Andan 72 ( ANDA) ; ibidem, 25 May 1995, Irma Suryani 34 ( ANDA) ; ibidem, 26 May 1995, Irma Suryani 50 ( ANDA) ; ibidem, 25 May 1995, Efdar Roza 19 ( ANDA) ; ibidem, 29 Nov. 1992, Isman Afandi 21 ( ANDA) ; Kabupaten Tanah Datar, Kecamatan X Koto, Cagar Alam Lembah Anai, 400–800 m, 1 June 2008,flowering, Ari Anggara & Rikinovtian Burlis 59 ( ANDA) ; Asam Pulau about 9 km from Lubuk Alung, 1 Nov. 1991, Mesli 084 ( ANDA) ; along river of Asam Pulau about 9 km from Lubuk Alung, 3 Nov.1991, Childa 12 ( ANDA) ; Kabupaten Padang Pariaman, Lubuk Alung, Asam Pulau, 60–250 m, 22–24 Mar.2002, Ade, Rizki, Indah, Icha, Lenmar & Yessi AP-08-027 ( ANDA) ; Padang, Ulu Gadut,along Sungai Gadut Gadang, 350–450 m, 2 Aug. 1984, M. Hotta, H. Okada & T. Kohyama 281 ( ANDA) ; Sumatra,sine loc.[presumably Padang Highlands], Curtis 115 ( K) ; culta Hort. Veitch. (from Curtis ), Aug. 1882, s.n. ( K) ; culta Hort. Veitch. (from Curtis ), 3 Sept. 1884, s.n. ( K) .

Note — Description and measurements based on living material Ardiyani et al. 189.