Eleiodoxa conferta, commonly known as kelubi, asam paya, or asam payak, is a monotypic palm species in the family Arecaceae that is native to the peat swamp forests of Southeast Asia, including parts of Thailand, Malaysia, Borneo, and Sumatra. The genus name Eleiodoxa is derived from the Greek eleio ("wet") and doxa ("home in"), referring to its natural swampy habitat, while the species epithet conferta—Latin for "crowded"—refers to the plant's dense, clustering growth habit. Historically, the plant has been an essential resource for local indigenous communities, providing materials for thatching and matting, as well as a reliable source of highly acidic, sour fruit that serves as a vital culinary and medicinal agent.

The plant is an acaulescent (stemless), dioecious, clustering palm. It thrives in humid, waterlogged peat environments and produces distinct, pear-shaped fruits, typically reaching up to 3 cm in length. These fruits are covered in a layer of tough, scaly skin that transitions from green to a dull yellow, brown, or red-orange as they ripen. Because the plant is dioecious, both male and female forms must be present for fruit production to occur. While it is an underutilized commercial crop, it is frequently found in regional traditional markets across its range, where it is valued for its unique flavor and functional properties.

The fruit of Eleiodoxa conferta is characterized by an intensely acidic and astringent flavor, making it a natural local substitute for tamarind (Tamarindus indica). It is rarely consumed raw due to its extreme sourness; instead, it is a staple ingredient in "sour" dishes like Masak Asam and Sambal Asam Payak. Culinary preparation typically involves peeling the fruit and pickling it in a salt-sugar solution to create a popular sweet-and-sour condiment. It is also commonly boiled to create sweetmeats or used as a flavoring agent in raw fish salads and spicy fish curries, providing a sharp tang that balances rich, fatty, or savory ingredients. The apical buds of the palm are also harvested and consumed as a vegetable, though this practice results in the death of the specific trunk harvested.

Nutritionally, the fruit is high in moisture and dietary fiber but very low in fat and protein. Its biochemical profile is increasingly the subject of research for its potential health-promoting properties, particularly regarding its high concentration of phenolic compounds and flavonoids, which contribute to strong antioxidant and enzyme-inhibitory activities in blood glucose regulation. In traditional ethnomedicine, various parts of the plant are utilized for their therapeutic potential. A decoction of the scaly fruit husk is a traditional remedy for treating coughs and hoarseness, while pounded stem decoctions and plant pastes are historically applied to relieve headaches or treat inflammatory conditions like orchitis.