Impatiens kachinensis Hook.f. ex Toppin

Smets, E. F. & Janssens, S. B., 2018, Balsaminaceae of Myanmar, Blumea 63 (3), pp. 199-267 : 229-230

23. Impatiens kachinensis Hook.f. ex Toppin — Map 10

Impatiens kachinensis Hook.f. ex Toppin (1920) 366;W.J. Kress et al. (2003) 170. — Type: Mokim s.n. (lecto, designated here K K000694658).

Terrestrial herb, 21–50 cm tall. Stem erect, simple to rarely branched, red, glabrous. Leaves spirally arranged. Petiole 5–20 mm long, glabrous. Lamina 54–140 by 12–23 mm, narrowly elliptic, apex acute to acuminate and mucronate, base cuneate, margin serrate, glabrous, with one pair of red clavate glands at petiole base; lateral veins 6–15 pairs. Inflorescence axillary, erect, 4–8-flowered raceme. Peduncle 25–75 mm long, glabrous. Rachis 7–25 mm long. Flowers 14–25 mm long, 22–32 mm deep, asymmetric, entirely light orange-yellow. Bracts 3.5–6 by 4–5 mm, elliptic, concave, apex acute, base

Map 10 Distribution of Impatiens holocentra Hand.-Mazz. (●), I. kachinensis Hook.f. ex Toppin (●), I. sarissiformis C.E.C.Fisch. (●) and I. chimiliensis H.F.Comber (●).

obtuse, margin entire, glabrous, caducous. Pedicel 13–20 mm long, glabrous. Lateral sepals 2, 4–4.5 by 2–2.5 mm, free, obliquely ovate, apex acute and mucronate, base cuneate to obtuse, glabrous. Lower sepal 7.5–10 by 4–7 mm, 10–15 mm deep, navicular, apex acute and mucronate, glabrous, dorsal part tapering into a straight to upcurved spur, 17–25 mm long. Dorsal petal c. 10 by 8 mm, obovate, flat, strongly reflexed backward, apex round, base cuneate, abaxial midvein simple. Lateral united petals 22–26 mm long, free, different in size and shape: the left upper petal c. 13 by 6 mm, broadly obovate, apex obtuse, base cuneate; the right upper petal c. 10 by 2–3 mm, oblong: the lower petals free; the left lower petal c. 14 by 4 mm, narrowly ovate, apex acute, base without auricle, glabrous; the right lower petal c. 20 by 2 mm, narrowly oblong to linear, apex acute. Stamens: filaments 3–4 mm long. Ovary 4 mm long, 1 mm diam, glabrous. Fruits linear, the seeds being in the upper portion only. Seeds 7–17.

Phenology — Flowering: September to March; fruiting: October to November.

Distribution — Endemic to Myanmar (Kachin State).

Ecology — Growing along the stream, in evergreen forest, 350–1000 m altitude.

Other collections examined. MYANMAR, Kachin State, Mokim s.n. (K000694657), upper Burma , Kachin Hills , Mar. 1898 ; Toppin 4286 (K H2015/00092 145, K H2015/00092 146) , Kachin Hills, Sumprang 1250’, Ban Kan 1400’, Kumtat 1450’, alt. 1250–1450 ft (381–442 m); Jin et al. PT­ ET 1027 (PE PE2472783*, PE PE2472784*), Putao, Hkamdaukmyit Camp, N27°36'48.91" E96°48'55.30", alt. 2457 m, 21 Oct. 2014 ; Jin et al. PT­ET 1403 (PE PE2472650*, PE PE2472651*, PE PE2472652*,PE PE2472653*, PE PE2472654*), Putao, Makohwa, 27 Oct. 2014; Jin et al. PT­ET 87 (PE PE2472757*, PE PE2472758*, PE PE2472759*, PE PE2472760*, PE PE2472761*, PE PE2472762*), Putao, Upper Shankaung , N27°25'52" E97°17'50", alt. 450 m, 12 Oct. 2014 .

Notes — Impatiens kachinensis is similar to I. drepanophora and I. sarissiformis , but differs in having narrowly elliptic lamina vs ovate ( I. drepanophora ) or linear-oblong ( I. sarissiformis ) lamina.

We found two sheets of Mokim s.n. annotated as I. kachinensis and select K000694658 because it has a complete dissected flower and good flower illustration.

Toppin (1920) recorded that I. kachinensis is visited by butterflies and bees, similar to I. racemosa ( Ruchisansakun et al. 2016) , I. drepanophora and I. longiloba Craib (Ruchisansakun, pers. obs).