Impatiens ekapaksiana Utami

Utami, N. Kew Bull (2012) 67: 731. https://doi.org/10.1007/s12225-012-9403-3

Type

Type: Indonesia, Sumatra, Mt Pantai Cermin, DedenGirmansyah 1536 (holotype BO!).

Habit

Perennial herb up to 35 mm tall; simple, rooting at the lower nodes, pubescent

Leaves

Leaves alternate, congested towards the apices of the stems, purple and sometimes green; lamina ovate, 4 – 55 × 8 – 27 mm, base acute, margin serrate to crenate, apex acute, lateral veins 3 – 7 pairs, venation obvious, pubescent, petiole 10 – 25 mm long, pubescent

Inflorescences

Inflorescences 1 or 2-flowered; flowers obvious, pubescent, petiole 10 – 25 mm long, pubescent, flowers yellow with a red blotch on the lower part

Peduncles

Peduncles c. 45 mm long, pubescent

Bracts

Bracts linear, 5 – 7 mm, pubescent

Pedicel

Pedicel c. 18 mm long, Lateral sepals 2, ovate to elliptic, 4 – 5 × 7 – 9 mm, reddish to yellowish, pubescent

Calyx

Lower sepal shallowly navicular, c. 5 × 10 mm, blotched with red inside, abruptly constricted into a filiform spur, 20 – 25 mm long, curved towards the tip, reddish to yellowish, pubescent

Corolla

Lateral petals united, upper part of each pair ovate to oblong, apiculate, c. 15 × 10 mm, yellow, lower part of each pair asymmetrical, ± ovate, c. 4 × 6 mm, yellow with red spot Dorsal petal shallowly cuculate, c. 5 × 10 mm, reddish to yellowish, pubescent

Ovary

Ovary glabrous

Fruits

Fruit a capsule, fusiform, c. 5 × 14 mm, glabrous

Figures

Figs 1 and 2.

Distribution

Endemic to Indonesia: West Sumatra. Known only from Mt Pantai Cermin in South Solok (1.16546°S, 100.51266°E).

Ecology

Growing along riverside; alt. 1600 m.

Conservation

The species only grows in this area and appears to be common only on Mt Pantai Cermin. The population needs to be assessed accurately before it can be classified as anything other than Data Deficient (DD) (IUCN 2001).

Phenology

Flowering May – Oct.

Note

Impatiens ekapaksiana typically has small yellow, red-marked flowers and finely pubescent peduncles, venations and petioles. I. ekapaksiana closely resembles I. sidikalangensis Grey-Wilson; they differ in floral details, the latter species having white or pale pink flowers, and a lilac purple stain on the dorsal petal and at the base of the two lateral petals. The species epithet is given in honour of TNI-KOPASSUS (the Indonesian Special Forces) for their dedication and encouragement to conserve the environment and biodiversity in Sumatra. Ekapaksiana is derived from ‘Bintang KarthikaEkaPaksi’, a sign of appreciation issued by the army of Indonesia.