|Leaves and opening flower|
(L.) Kurz 
Barringtonia asiatica (fish poison tree, putat or sea poison tree) is a species of Barringtonia native to mangrove habitats on the tropical coasts and islands of the Indian Ocean and western Pacific Ocean from Zanzibar east to Taiwan, the Philippines, Fiji, New Caledonia, Solomon Islands, the Cook Islands, Wallis and Futuna and French Polynesia. It is grown along streets for decorative and shade purposes in some parts of India, for instance in some towns on southeastern shore. It is also known as Box Fruit due the distinct box-shaped fruit it produces. The local name futu is the source of the name for the Polynesian island Futuna. The type specimen was collected by botanist Pehr Osbeck on a sandy beach area on the island of Java, later to be described (and given the original name of Mammea asiatica) by Carl Linnaeus in his Species Plantarum in 1753.
It is a small to medium-sized tree growing to 7–25 m tall. The leaves are narrow obovate, 20–40 cm in length and 10–20 cm in width. Fruit produced as mentioned earlier, is otherwise aptly known as the Box Fruit, due to distinct square like diagonals jutting out from the cross section of the fruit, given its semi spherical shape form from stem altering to a subpyramidal shape at its base. The fruit measures 9–11 cm in diameter, where a thick spongy fibrous layer covers the 4–5 cm diameter seed.
The fruit is dispersed in the same way as a coconut – by ocean current – and is extremely water-resistant and buoyant. It can survive afloat for up to fifteen years; it was one of the first plants to colonise Anak Krakatau when this island first appeared after the Krakatau eruption. When washed ashore, and soaked by rainwater, the seeds germinate.
All parts of the tree are poisonous, the active poisons including saponins. Box fruits are potent enough to be used as a fish poison. The seeds have been used ground to a powder to stun or kill fish for easy capture, suffocating the fish where the flesh is unaffected.
Its large pinkish-white, pom pom flowers give off a sickly sweet smell to attract bats and moths which pollinate the flowers at night.
- World Conservation Monitoring Centre (1998). "Barringtonia Asiatica". IUCN Red List of Threatened Species (IUCN) 1998: e.T31339A9627718. Retrieved 23 Mar 2016.
- Under its treatment as Barringtonia asiatica (from its basionym Mammea asiatica L.), this species was published in Preliminary Report on the Forest and other Vegetation of Pegu App. A: 65. 1875. "Name - Barringtonia asiatica (L.) Kurz". Tropicos. Saint Louis, Missouri: Missouri Botanical Garden. Retrieved November 1, 2011.
- "Barringtonia asiatica (L.) Kurz". World Checklist of Selected Plant Families (WCSP). Royal Botanic Gardens, Kew. Retrieved 23 Mar 2016 – via The Plant List.
- Ria Tan (2001). "Sea Poison Tree". Mangrove and wetland wildlife at Sungei Buloh Nature Park. Singapore. Retrieved November 1, 2011.
- GRIN (October 1, 2010). "Barringtonia asiatica information from NPGS/GRIN". Taxonomy for Plants. National Germplasm Resources Laboratory, Beltsville, Maryland: USDA, ARS, National Genetic Resources Program. Retrieved November 1, 2011.
- Thiel, M. & Gutow, L. (2004). "The ecology of rafting in the marine environment. I." (PDF). Oceanography and Marine Biology: An Annual Review 42: 181–263. doi:10.1201/9780203507810.ch6. Accessed 2009-05-31.
- Smith, S. Percy. "Futuna, or Horne Island, and Its People". The Journal of the Polynesian Society, Vol. 1, No. 1, pp. 33 – 52. 1892
- Mammea asiatica L. (the basionym to Barringtonia asiatica) was originally described and published in Species Plantarum 1: 512–513. 1753. "Name - Mammea asiatica L.". Tropicos. Saint Louis, Missouri: Missouri Botanical Garden. Retrieved November 1, 2011.
- Flora of China: Barringtonia asiatica
- Tsou, C-H., and Mori, S.A. "Seed coat anatomy and its relationship to seed dispersal in subfamily Lecythidoideae of the Lecythidaceae (The Brazil Nut Family)." Botanical Bulletin of Academia Sinica. Vol. 43, 37-56. 2002. Accessed 2009-05-31.
- Thaman, R.R. "Receptors Batiri kei Baravi: The ethnobotany of the Pacific island coastal plants." Atoll Research Bulletin. Vol. 361, 1-62. May, 1992. Accessed 2009-05-31.