The type specimen of this enigmatic climber species was collected from Perak by Sir George King’s collector. King first named it Zanonia clarkei in 1898, after Charles Baron Clarke, a British lawyer-botanist that authored the Cucurbitaceae account in Hooker’s Flora of British India. The species was then moved from genus to genus by different authors, namely to Macrozanonia in 1916 by Belgian botanist Alfred Célestin Cogniaux, back to Zanonia in 1922 by Henry Nicholas Ridley, into Alsomitra in 1942 by John Hutchinson, until finally place in a monotypic genus by Willem Jan Jacobus Oswald de Wilde. The current genus name is in honour of Baya Busu (1956–2002), a late forester from the Temuan aborigine’s community that worked at the Kepong Herbarium, as Dr. de Wilde recalled Baya’s bravery in climbing unaided to impossible heights to obtain the fruiting specimens.
This is a relatively slender climber, but has 20–30 m long vines hanging from lofty canopy trees. These vines are grooved, with reddish brown powdery hairs near the shoots and raised leaf scars on older parts. The rather long and springy tendrils are branched with disc-like adhesive pads at the tips. The leaves are wedge to heart shaped in adult plants, while appearing “spiky” in saplings with some sharply-pointed lobes along the leaf margin. The genus is dioecious, meaning male and female flowers grow on separate plant individuals. Male plants have small but attractively red, shallowly cup-shaped flowers with creamy yellow anthers in the centre. To date the female flower has yet to be seen. The fruit is a large, cylindrical, pendent capsule with numerous membranous, winged seeds.
The regenerated forest at the canopy walkway of FRIM is home to a small population of Bayabusua clarkei. Elsewhere it is known from Baling (Kedah), Tapah (Perak) and Ulu Langat (Selangor), and is accorded a Near Threatened status. As one walks through the forest floor, only thin and almost featureless vines are visible, it is therefore hard to imagine that high up in the canopy some hundred feet or so above ground, this bizarre relative of the cucumber has pretty dark red flowers and foot-long, bell-shaped fruits.
