Impatiens pseudolaevigata Gogoi, B.B.T.Tham & Lidén, 2017

Impatiens pseudolaevigata Gogoi, B.B.T.Tham & Lidén View in CoL , sp. nov. ( Figure 1 A, A 1 View FIGURE 1 , A 2, E and 2 View FIGURE 2 )

Differs from Impatiens laevigata var. laevigata in having reddish brown to deep green concave orbicular bracts ( Fig. 1, A1 View FIGURE 1 & Fig. 2 View FIGURE 2 , D), smaller lateral sepals terete with slightly widened base ( Fig. 1 View FIGURE 1 , A 2 View FIGURE 2 & Fig. 2 View FIGURE 2 , E), a dorsal petal as long as wide, lack of a dorsal ridge in the dorsal petal ( Fig. 2 View FIGURE 2 ,H), lack of red veins on the distal lobe of the lateral united petals ( Fig. 2. J View FIGURE 2 ), and presence of a short abruptly curved hooked spur with a red tip ( Fig. 2 View FIGURE 2 , G). Also differs from I. laevigata var. grandifolia Hook. f. (1910: 299) in having reddish to deep green concave orbicular bracts ( Fig. 1, A1 View FIGURE 1 & Fig. 2 View FIGURE 2 , D), a dorsal petal as long as wide and lack of a dorsal ridge ( Fig. 2 View FIGURE 2 , H) on its back, smaller lateral sepals ( Fig.2 View FIGURE 2 , E), and an abruptly curved hooked spur with a red tip ( Fig.2 View FIGURE 2 , G; Table 1 View TABLE 1 ).

Type: — INDIA. Arunachal Pradesh, West Kameng, Nichifu , 1800 m, 22 Oct 2014, R. Gogoi & B.B.T. Tham 21965 (holotype CAL! , isotype CAL! , ASSAM! ).

Perennial herbs up to 100 cm tall, underground organs consisting of a root clump. Stem sparsely branched, glabrous, green, nodes not swollen. Leaves mainly in the upper portion of the stem, alternate, petiole to 6 cm long, green, petiole base exstipulate. Lamina elliptic, 6 ‒ 20 × 2 ‒ 8 cm, glabrous, base cuneate, margin crenate, setose between teeth, lateral veins 6 ‒ 10 pairs, subopposite. Inflorescence axillary, pendent, peduncle to 2 cm long, green, glabrous, 2-flowered, bud reddish or green; pedicel to 2 cm long, green, glabrous; bracts orbicular to broadly ovate, strongly concave, amplexicaul, glabrous, 1 cm long, to 1.5 cm wide, reddish brown to green, caducous, margin entire, apex mucronate. Lateral sepals 4, one pair large and similar to bract, another pair small; outer lateral sepals orbicular, 1.7 ‒ 2 × 1.5 ‒ 2 cm, reddish brown to green, concave, apex with thick prominent mucro, margin entire, membranous; inner sepals greenish white, 2 mm wide at very base, constricted into terete 5-mm long portion. Lower sepal sub-bucciniform, yellow, with red veins inside, to 2 cm deep, spur hooked, yellow at base, distal portion red. Dorsal petal yellow, ovate-subtriangular with short whitish claw, 1.7 ‒ 2 × 1.6 ‒ 2 cm, apex acute or slightly acuminate, dorsally not ridged. Lateral united petals yellow with whitish base, bilobed, lobes sub-equal, whole up to 3.6 cm long, basal lobe obovate, not clawed, to 1.6 cm long, to 1.1 cm wide, apex acute, yellow with prominent reddish or orange blotch, dorsal auricle absent or inconspicuous; distal lobe unevenly dolabriform, to 2.6 cm long, to 0.8 cm wide. Stamens 5, encircling ovary, to 3 mm long, anther lobe obtuse. Capsule linear, slightly turgid at the middle, smooth, green, to 3.5 cm long, seeds few, 2 mm, surface warty.

Phenology —Flowering and fruiting July to November.

Etymology —The species epithet is coined to denote its superficial similarity with Impatiens laevigata .

Distribution and ecology —In moist forest floor near streams in subtropical evergreen forest along with Impatiens racemosa and Elatostema sp. The species is encountered in three places with populations of many individuals and no threat of existence is apparent.

Additional specimens examined (paratypes): — INDIA. Arunachal Pradesh, West Kameng, Zero Point area , 27 September 2013, BBT Tham 35914 ( ARUN) .