''Quassia harmandiana'' is a freshwater mangrove shrub or small

tree In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are ...

in the Simaroubaceae

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

. It is found in Cambodia, Laos and Vietnam. The wood provides firewood. Certain fish eat the poisonous fruit

Description

This species grows as a shrub or small tree, some 5 to 8m tall. The species was placed in the section Samadera by Noteboom, along with '' Quassia indica''. The plants of this section have simple leaves with roughly scattered concave glands, mostly on the under surface. The flowers are bisexual, occurring in axillary or terminal inflorescences, either pseudoumbels with peduncles or in racemes. There are 3-5 calyx lobes, these are imbricate in the bud, obtuse and have a concave gland in the centre. There are 3-5 contorted petals, much longer than the calyx, usually hairy on the underside. The disc is large, as high as it is broad, and gynophore-like. The style has a inconspicuous terminal stigma. The quite large fruits are compressed laterally, with a narrow, thinner, sharp-edged part in the apex half. ''Quassia harmandiana'' fruit are very large and dorsoventrally compressed. It flowers from March to May and fruits in July. The fruit are poisonous, see below.

Distribution

The species grows in the following countries: Cambodia, Laos, Vietnam.

Habitat, ecology

The plant grows in the mangrove and back-mangrove formations of the

Mekong The Mekong or Mekong River is a trans-boundary river in East Asia and Southeast Asia. It is the world's List of rivers by length, twelfth longest river and List of longest rivers of Asia, the third longest in Asia. Its estimated length is , ...

and Tonle Sap rivers and lake. In the vegetation communities alongside the Mekong in Kratie and Steung Treng Provinces, Cambodia, this taxa is moderately abundant in the dense diverse strand community (last to be flooded each year, first to drain). It also occurs in mixed evergreen and deciduous forests in the area. It grows on soils derived from metamorphic sandstone bedrock, at 25-30m altitude. In the Khone Falls section of the Mekong, in southern Laos, close to where the river becomes fully Cambodian, two species of carp-like fish, ''

Leptobarbus hoevenii Hoven's carp (''Leptobarbus hoevenii''; ''Jelawat'' in Malay), also known as the mad barb or sultan fish, is a species of fish in the barb family. It is native to freshwater habitats in the Thai-Malay Peninsula, Borneo and Sumatra. Populations ...

'' and '' Tor cf. tambra'' eat the fruits of this species. The flesh of these fish is rendered poisonous after eating this and other fruit. In ''Tor'' cf. ''tambra'' the eyes become red and scales become whiter if poison is present, and if recognised, then the fish can be made edible by discarding the head and guts, then dried in the sun or marinated.

Vernacular names

''Krahs'' and ''kra:'' ( Khmer) are names used in Cambodia. ''Mak ngooan'' is a name from Laos.

Uses

The wood makes excellent firewood. The plant contains bactericidal compounds.

History

The Nederlander botanist, taxonomist and editor of '' Flora Malesiana'' (since 1999), Hans Peter Nooteboom (born 1934), described the species in 1962 (published in 1963) in his article "Generic delimitation in Simaroubaceae tribus Simaroubeae and a conspectus of the genus Quassia L.", in the journal '' Blumea''.

References

{{Taxonbar, from=Q15545672 harmandiana Flora of Cambodia Flora of Laos Flora of Vietnam Flora of Indo-China Plants described in 1963