Impatiens florulenta Hook.f.

Smets, E. F. & Janssens, S. B., 2018, Balsaminaceae of Myanmar, Blumea 63 (3), pp. 199-267 : 239-240

39. Impatiens florulenta Hook.f. — Fig. 16; Map 14; Plate 3e

Impatiens florulenta Hook.f. (1905) 25, 32; W.J. Kress et al. (2003) 169. — Type: Khalil s.n. (lecto, designated here K K000694673), Myanmar, southern Shan State, Saga , 1893.

Impatiens curvipes sensu T. Shimizu (1970) 196, non Hook.f.

Terrestrial, annual herb, 15–45 cm tall. Stem erect, cylindrical, 2–4 mm diam, sometimes swollen at nodes, richly branched, red to green, glabrous, remotely pilose towards apex. Leaves decussate at first basal node, otherwise spirally arranged, usually congested at apex of stem. Petiole 15–45 mm long, c. 1 mm diam, angular, green to pink, nearly glabrous, remotely pilose. Lamina 40–60 by 20–35 mm, ovate to elliptic, apex acute to acuminate, base attenuate, margin serrate, adaxial green and pilose, abaxial pale green and remotely pilose, with 3–many long red hairs along the margin near the base; lateral veins 4–6 pairs. Flowers solitary, axillary, erect, 19–25 by 10–13 mm, 20–25 mm deep, pink with white centre. Bracts c. 1 by <1 mm, linear to narrowly lanceolate, apex acute and mucronate, base cuneate, green with red apex, persistent. Pedicel 25–27 mm long, c. 1 mm diam, red to green, pilose. Lateral sepals 2, c. 1 by <1 mm, free, linear to narrowly lanceolate, apex acute, base obtuse, pale green with red tip, glabrous. Lower sepal 7–8 by 3–4 mm, 3–4 mm deep, navicular, apex acuminate

Fig. 16 Impatiens florulenta Hook.f. a. Habit; b. front view of flower; c. lateral view of flowers; d. fruit; e. pedicel and ovary; f. stamens ; g. lower lateral sepals; h. lower sepal; i. dorsal petal; j. lateral united petals. — Drawn by Saroj Ruchisansakun.

and mucronate, white to pale pink, pilose outside, distal part gradually tapering into a straight spur, 15–16 mm long, pink with red tip. Dorsal petal 7–8 by 8–9 mm, obovate to broadly obovate to orbicular, cucullate, apex emarginate, base obtuse to round, pink, glabrous with pilose midrib, abaxial midvein with a keel-shaped crest, c. 3 mm wide, pink to white. Lateral united petals 14–15 mm long, free: the upper petals c. 6 by 4–5 mm, orbicular to obovate, apex round, base cuneate, pink with white base, and deep pink lines at the base; the lower petals 11–12 by 6–7 mm, free, broadly lanceolate to broadly ovate to broadly elliptic, apex unequally bilobed, pink with white base, sometimes with small yellow mark at the base. Stamens: filaments c. 4 mm long, white to pink; anthers pink. Ovary 4 mm long, c. 1 mm diam, 5-carpellate, green, pilose. Fruits 10–11 mm long, 4–5 mm diam, fusiform, 5-lobed, green, pilose with short hairs. Seeds 17–20, c. 1.5 mm long, ovoid, brown.

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

Distribution — Myanmar (Shan State), northern Thailand.

Ecology — Growing in open or shady areas in mix deciduous forest, 1150–1300 m altitude.

Other collections examined. MYANMAR, Shan State, Ruchisansakun et al. 736 (L L2071132, MAND, RAF), Taunggyi District , N21°08'00.68" E96°24'44.97", alt. 1150 m, 29 Sept. 2015 .

Notes — Impatiens florulenta is most similar to I. curvipes but differs in having a cucullate dorsal petal, a spreading or slightly recurved pedicel in fruiting stage, and fruits with short hairs, while I. curvipes has a flat dorsal petal and strongly decurved pedicel in fruiting stage. Hooker (1905) mentioned that this species is characterized by a glabrous fruit, yet the type specimen has pilose fruits (with short hairs). The population in Thailand was misidentified as I. curvipes ( Shimizu 1970) .

Similar to many taxa in Hooker (1905), Hooker did not designate a type of I. florulenta . We found only one specimen (with an illustration), Khalil s.n. (K000694673), on which the name I. florulenta is based and which matches the protologue, except pilose fruits, so we selected it as lectotype.