Description

Description. Perennial woody liana, 8 - 12 m high. Stem terete, circular in cross section, ca. 1 cm in diam., young branches green, sparsely pubescent, becoming glabrescent, bark deeply irregularly longitudinally fissured when mature, internodes 7 - 15 cm long. Petiole 3.5 - 6.0 cm long, twisted, pubescent. Leaf blade ovate or ovate-lanceolate to narrowly ovate, subcoriaceous, 15 - 31.5 x 5.8 - 12.5 cm, base rounded to slightly cordate, apex acuminate, margin entire, both surfaces densely villous when young, then the adaxial surface dark-green and glabrous, the abaxial surface densely villous; basal veins five, palmate, secondary veins four to six pairs, pinnate; tertiary veins coarsely reticulate, slightly sunken adaxially, prominent abaxially. Inflorescence cymose on old woody stems and young branches, solitary or two cymes, each cyme with one or two flowers, clearly separated from each other. Inflorescence axis 2 - 6 mm long, tomentose. Bracteole clasping the axis, ovate-triangular, 2 - 4.5 x 1.5 - 2 mm, subsessile, both surfaces densely brown villous. Pedicel 1.3 - 1.6 cm long, pendulous, densely brown villous. Ovary oblong, 1.5 - 1.7 x 0.3 - 0.4 cm, densely brown villous. Perianth horseshoe-shaped (in lateral view), 6.5 - 7.5 cm high, claret (deep purple red), outside densely brown hirsute with parallel dark purple veins, inside glabrous to white villous. Utricle distinct from the tube, bell-shaped, 2.3 - 2.5 cm high, 1.2 - 1.3 cm in diam. at base, 1.6 - 1.8 cm in diam. at apex, inside vinaceous (purplish red) with densely white trichomes. Tube horseshoe-shaped, 8.3 - 8.5 cm, uniformly claret (deep purple red), with visible dark purple veins, lower tube strongly inflated, saccate, 2.5 - 2.7 cm high, 1.8 - 2.0 cm in diam. and upper tube obliquely shortened funnel-shaped, parallel to the utricle, inner surface stramineous dyed with purple red patches, 3 - 3.5 cm high, narrower at base, 1 - 1.1 cm in diam. and broader at apex, 1.3 - 1.4 cm in diam. Limb discoid-rotund or trumpet-shaped, 4.2 - 4.8 cm high, 4 - 4.4 cm wide, with three subequal lobes, valvate preanthesis, lobes broadly ovate-triangular, each 3.3 - 3.8 cm wide, 1.8 - 2.2 cm high, margins of all lobes revolute during anthesis, warty on inner surface of lobes dark purple. Throat deep purple red, glabrous, without dots. Annulus present. Gynostemium with trilobed stigma on top, 7 - 7.5 x 5.5 - 6.5 mm in diam., anthers 6 in 3 pairs, oblong, 4.3 - 4.5 x 1.2 - 1.4 mm, yellow. Fruit and seeds were not seen.

Common Names

Taxonomic Hierarchy

Kingdom: Plantae

Phylum: Tracheophyta

Class: Magnoliopsida

Order: Piperales

Family: Aristolochiaceae

Genus: Isotrema

Species: Aristolochia sinoburmanica Y.H.Tan & B.Yang