Identification:
The plant is characterized by a tuberous, swollen stem base that is stout and has a hard, non-spiny, but rough, yellowish-gray, nearly round structure. These can reach up to 25 cm in length and are glabrous (without hairs). The outer layer has numerous honeycomb-like perforations, potentially providing shelter for ants. From the swollen stem base, 2-4 smooth, nearly four-sided, glabrous stems emerge. Opposite leaves are present with a tapering base and a blunt tip. The leaf blades are thick, smooth, glossy, and without hairs, measuring 3.5-15 cm long and 2-7 cm wide. Secondary veins are slender, numbering 7-10 pairs. The petioles are short, smooth, and 0.5-2.5 cm long. Stipules are small and pointed. Flowers are sessile (without stalks) and typically clustered in groups of 3-5 in the leaf axils. The calyx is tubular, with a short limb at the apex. The corolla is white, with a corolla tube 2.5-3 mm long, and has 4 oval-shaped lobes at the tip. There are 4 stamens, attached at the throat of the corolla tube. The stigma is thick and hairy. The fruits are small, with a hard seed, and oval-shaped. When ripe, they are orange, measuring 6-7 mm long. There are 2 seeds, each 2 mm long. (Picture 245).
Biology and Ecology:
Flowering occurs from December to January (the following year), with fruiting from January to March. Reproduction is by seed. The plant is epiphytic, growing on woody trees in humid tropical forests and sometimes in sparse forest types, at altitudes of approximately 700 m.
Distribution:
- Vietnam: Kontum (Kon Plông), Gia Lai (An Khê), Đắk Lắk, Đồng Nai, Lâm Đồng (Bảo Lộc), Quảng Ngãi (Sơn Hà), Bà Rịa – Vũng Tầu (Xuyên Mộc), Bù Gia Mập National Park, Bình Phước, Kiên Giang (Phú Quốc).
- Worldwide: India, Malaysia, Indonesia.
Value:
The plant is unique in terms of its genetic value due to its unusual life form. The swollen stem base is used in traditional medicine to treat liver diseases, jaundice, musculoskeletal pain, act as a diuretic, and reduce inflammation.
Status:
The plant is sparsely distributed. Deforestation and timber exploitation have directly resulted in a reduction in the plant’s distribution area and the loss of host trees. Additionally, the plant grows and develops slowly, and unsustainable harvesting practices further diminish the seed source.
IUCN Red List Category: EN A1b,d, B1+2b,e.
Conservation Measures:
Further surveys are needed to identify and protect locations with relatively concentrated populations. More detailed biological research is required to enhance the effectiveness of conservation efforts.