Aristolochia assamica - Assam Pipevine

Assam Pipevine is a newly discovered (2019) twining herb, with branches round, twisted, purplish to greenish, 4-15 cm long, hairless. Leaf-stalks are 5-10 cm long, slender, twisted, hairless. Leaf blades are triangular to triangular heart-shaped, 7.5=17 x 5.5-12.5 cm, papery, margin entire, both surfaces hairless, tapering, base heart-shaped; veins palmately 7-nerved from base. Flowers are borne in leaf-axils, in 2-15-flowered bundles. Flowers are 4-4.5 cm across. Flower-stalk 1-1.5 cm long, slender, curved, hairless. Flowers are creamy-white to greenish-yellow with yellowish striations, below hairless, above densely velvet-hairy with hairs curving downwards. Utricle spherical, distinctly delimited from tube, 6-7 x 6-7 mm, stalkless. Tube bent upwards, rectilinear, 12-17 x 5-8 mm. Limb 1-lobed, oblong linear, 6-7 x 10-11 mm, with a brownish patch on throat and a twisted cauda at tip, 5-17 mm long, inner surface of limb and mouth velvet-hairy. Capsules are elliptic-oblong, hairless, about 10 x 1.5 cm, with 6 longitudinal ridges. Assam Pipevine is known only from two localities in Papum Pare District, Arunachal Pradesh and the Behali Reserve forest, Assam. Flowering: October-December.