Lasia spinosa is an obscure member of the yam family, Araceae. The common names of this plant that I have come across include simply lasia, unicorn plant (probably due to the appearance of its inflorescences) and geli-geli (in Malay). It is a perennial tropical plant that is native to India, Southern China and Southeast Asia.
It is a large herbaceous plant that can grow up to 2 m tall. Like many plants in the yam family, the leaves of Lasia spinosa rise from the base and are arranged like a rosette. Each leaf is divided into several lobes and numerous small spines arm the leaf stalk and along the veins found at the back of leaves. Plants grow and spread via underground stems which are rich in starch.
Visually, Lasia spinosa is largely a plain green plant and is saved by its attractive, curious-looking inflorescence. Typical of an aroid, the real flowers are borne on a spike-shaped spadix. Unlike most other aroid species, the spathe of Lasia spinosa is not sail-like. The tip of the spathe is long and extended, twists along its length and held erect above the plant. Fruits of this plant are each aggregated on a club-like structure.
This aroid is an aquatic plant that thrives in a location with semi-shade to full sun. Naturally, it grows along the banks of rivers and in swamps and is tolerant of waterlogged conditions. It is edible and grown as a vegetable. Raw parts of the plant are documented to contain toxic constituents such as hydrocyanic acid and calcium oxalate and must be processed such as by cooking prior consumption. As a vegetable, the young tender leaves of Lasia spinosa are peeled to remove the spines. In Thailand, the young leaves are severed with ‘nam phrik plaa raa’ (spicy fermented fish sauce), stir-fried or added to hot and sour soup.
Like many other plants, Lasia spinosa has medicinal properties. Both the rhizomes and leaves possess expectorant properties. The latter also help ease stomachaches. The roots are boiled and the water used to bath newborn babies. The leaves are also used for the treatment of coughs, stomachache and various aches and pains.
The genus Lasia has been believed to be a monotypic genus until 1997 when a wild population of anew species, Lasia concinna, was discovered in a paddy field in West Kalimantan in Indonesia. Like Lasia spinosa, the farmer there had been growing them for its edible young leaves. This Lasia species had been known of previously only from a single specimen at the Bogor Botanic Gardens. At the time specimen was believed to have been a hybrid between Lasia spinosa and Cyrtosperma merkusii. The subsequent discovery by Hambali and Sizemore led to the realization that it was in fact a new species.