Henckelia siangensis - Siang Henckelia

Siang Henckelia is a newly described (2020) species remarkably different from all other species of Henckelia by its 5-winged sepal-cup and elliptic-ovate sepals. It has hairless stem and leaf-stalk and lanceshaped bracts, and can be easily distinguished by ovate to lanceshaped blade with finely toothed to minutely toothed margins, flower-cluster-stalk 4-8 mm, hairless, bracts persistent, sepals elliptic to ovate, raised at margins forming wings. Flowers are 4.5-5 x 1.4-1.8 cm, bright yellow with three dark yellow and maroon stripes per lobe near throat, more prominent on lower lip, glandular velvet-hairy inside, distinctly 2 lipped, lips divergent; upper lip 2-lobed, equal, broadly ovate, 4-6 x 5-7 mm, tip round, margin entire; lower lip 3-lobed, lobes nearly equal, broadly ovate, 7-10 x 5-6 mm, tip round, margin entire; tube 2.8-3.5 x 1.3-1.7 cm. Stamens are 2, inserted 2-2.3 cm above flower base, anthers and top of filaments maroon, glandular velvet-hairy. Flowers are glandular velvet-hairy inside and have glandular hairy style. Sepal-cup is green, bell-shaped, 5 winged, raised at the fusion of the sepals, splitting with maturity, later turning 5 lobed up to below middle of the tube, hairless, veins obscure, tube 6-7 mm long. Sepals are 2.0-2.3 x 0.6-1.1 cm, elliptic-ovate. Flowers are borne singly in leaf-axils, on 2-3 cm long stalk. It is an erect perennial, stemmed herb, 15-40 cm high, stems branched; mature stem round, about 5 mm across, hairless, young stem reddish brown, cylindrical. Leaves are decussate; leaf-stalk round, 1-6 x 0.1 cm, fleshy; blade ovate to lanceshaped, 7-10 x 2.5-4.5 cm, oblique-blunt base, pointed to shortly tapering at tip, margin finely toothed-minutely toothed, sparsely hairy on both surfaces, dark green above, pale green below; secondary veins 6-10 pairs. Siang Henckelia is only known, as of now (2020), from East Siang district of Arunachal Pradesh. Flowering: April.