Quassia indica), the bitter wood or Niepa bark tree, is a species of plant in the family Simaroubaceae.

It is a shrub or tree and grows primarily in wet tropical regions, from west Africa, through India, then down through Indonesia to Malesia.

[4][10] There is no heartwood, and the bark has small pores, the medullary rays are very fine, uniform and closely packed.

[6][3] Leaves simple, elliptic, ovate or obovate, 5–25 cm long, 2–8.5 cm wide, rounded to acuminate at apex, rounded or obtuse at base, glabrous, glandular beneath, densely reticulate-veined; petiole 7–15(–30) mm, often curved.

[2][3] Samadera indica has fruit of 1–4 carpels, each a woody drupe, ellipsoid with a unilateral thin wing in the upper part.

[5][9][8] Fruits are grouped in whorls of 1-4 carpels, and are green blotched red, ovoid, and flattened.

[4] It has several English common names such as; Niepa bark tree,[3] Bitter wood,[9] and Rangoon creeper.

[13] Depending on the country and language, it is also known as various names such as; in Hindi as लोखंडी and Lokhandi,[citation needed] in Kannada as ನೀಪಾ and Nipa, samdera,[3] or Kaduhonge,[14] in Malayalam as Karinghota,[15] കര്ംഗൊടാ Karinjotta, Karingota,[3] Karingotta,[10] or Njotta.

In Malaysia as kayu pahit (Peninsular), kelapahit (Murut, Sabah), manuggal (Iban, Sarawak).

[6] The botanic name of Samadera indica was first published and described by German Botanist Joseph Gaertner (1732–1791) in his seminal book De Fructibus et Seminibus Plantarum vol.2 on page 352 in 1791.

and Simarouba Aubl..[19][20] In 2007, DNA sequencing, and phylogenetic analyses was carried out on members of the Simaroubaceae family.

The woody and floating nature of the Samadera indica fruit explains how the species was able to be widespread across its distribution range.

[26] Samadera indica has been assessed for the IUCN Red List of Threatened Species in 2019.

[24] It can be cultivated for use in parks or gardens, due to its attractive foliage, fruits and general form.

[9][32] In Sri Lanka, a mixture of powdered bark or wood scrapings in warm water or coconut oil used to treated fever.

[43] In the Philippines, the bark and wood, are macerated in water, alcohol, or wine which is then said to have tonic, stomachic, anticholeric, antifebrile, and emmenagogue properties (used to stimulate blood flow in the pelvic area and uterus).

Also the macerated leaves are mixed with coconut oil are applied to the hair to kill lice, and an infusion of the seeds is utilized as a antipyretic (substance that reduces fever).

[41] The extracts were evaluated for antimicrobial effect using two strains of bacteria – Escherichia coli and Staphylococcus aureus and two species of fungi – Aspergillus niger and Candida albicans.

[32][57] Various extracts, including Samadera indica leaf extracts have shown to significantly decrease the reproduction ability of mosquitoes and also the hatchability of their eggs, in species such as Culex quinquefasciatus, Anopheles stephensi and Aedes aegypti.

[58] The macerated leaves, are mixed with coconut oil, then applied to the hair for cleansing purposes.

[60] The wood of the tree is used locally for example in the state of Sarawak in Malaysia, where it is used for making knife-handles,[29] such as parang handles.