Impatiens micromeris Hook.f.

Smets, E. F. & Janssens, S. B., 2018, Balsaminaceae of Myanmar, Blumea 63 (3), pp. 199-267 : 217

7. Impatiens micromeris Hook.f. — Fig. 11; Map 5

Impatiens micromeris Hook.f.(1905) 26; W.J. Kress et al.(2003) 170. — Type: Brandis s.n. (lecto, designated here K K000694789), Myanmar, Tenassarim.

Annual herb, 18–20 cm tall. Stem erect, c. 2.5 mm diam, richly branched. Leaves spirally arranged. Petiole 16–22 mm long, c. 1 mm diam. Lamina 25–31 by 12–15 mm, ovate to elliptic, apex acute to acuminate, base attenuate, the margin crenate, pilose on both sides, with one small and inconspicuous gland on each side of margin near lamina base; lateral veins 4 or 5 pairs. Inflorescence axillary, erect, solitary. Flowers c. 10 by 7 mm, c. 10 mm deep. Bracts linear, apex acute, base cuneate, margin entire, glabrous, persistent. Pedicel 14–17 mm long, <1 mm diam. Lateral sepals 4: the upper pair c. 0.5 mm by <0.5 mm, narrowly elliptic, apex obtuse to acute, base cuneate, glabrous; the lower pair free, c. 2 by 1 mm, ovate, apex acute and mucronate, base obtuse. Lower sepal c. 2.5 mm long, 2.5 mm deep, navicular, apex acute and mucronate, glabrous, distal part gradually tapering into a straight or curved slender spur, c. 5 mm long, with a single tip. Dorsal petal c. 5 by 3.5 mm, ovate to elliptic to oblong, apex round and mucronate, base obtuse, glabrous. Lateral united petals 9.5–10 mm long, connate: the upper petals c. 3 by 2 mm, ovate to obovate, apex round, base cuneate; the lower petals 8–8.5 by 3.5–4 mm, connate, ovate, apex obtuse to acute, base without auricle. Stamens unknown. Ovary c. 1.5 mm long, c. 0.5 mm diam. Fruits c. 5 mm long, 2 mm diam, fusiform. Seeds 1.5 mm long.

Phenology — Flowering: September.

Distribution — Endemic to southern Myanmar (Tenassarim, possibly Tanintahryi Region, Mon State, Kayin State).

Ecology — Unknown.

Note — The authors have not seen I. micromeris in situ. The species was described only from the type specimen. Hooker (1905) published this species with an identification key of other Impatiens and their locality but did not provide a detailed description.