''Avicennia alba'' is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of tropical

mangrove A mangrove is a shrub or tree that grows in coastal saline water, saline or brackish water. The term is also used for tropical coastal vegetation consisting of such species. Mangroves are taxonomically diverse, as a result of convergent evoluti ...

in the

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 ...

Acanthaceae Acanthaceae is a family (the acanthus family) of dicotyledonous flowering plants containing almost 250 genera and about 2500 species. Most are tropical herbs, shrubs, or twining vines; some are epiphytes. Only a few species are distributed in tem ...

. It is found growing in coastal and estuarine locations in India, Southeast Asia, Australia, and Oceania.

Description

''A. alba'' forms a low, dense bushy crown often branching near the base of the trunk. The shrub does not grow more than about high. The roots are shallow and send up a large number of pencil-shaped

pneumatophore Aerial roots are roots above the ground. They are almost always adventitious. They are found in diverse plant species, including epiphytes such as orchids (''Orchidaceae''), tropical coastal swamp trees such as mangroves, banyan figs (''Fic ...

s. These aerial roots help with gas exchange and also play an important part in the exclusion of salt from the plant's

vascular system The blood circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the entire body of a human or other vertebrate. It includes the cardiovascular system, or vascular system, tha ...

. The trunk has smooth, greenish-black bark that is finely fissured and does not flake. The dark green leaves, long and wide, have a silvery grey underside and grow in opposite pairs. The small, orange yellow flowers, borne in a racemose inflorescence, have four petals and a diameter of about when expanded. The fruits are greyish-green capsules and conical in shape with an elongated beak up to long. Each contains a single seed.Api Api Putih
Mangrove and Wetland Wildlife at Sungei Buloh Nature Park. Retrieved 2012-02-07. In the

Malay language Malay (; ms, Bahasa Melayu, links=no, Jawi alphabet, Jawi: , Rejang script, Rencong: ) is an Austronesian languages, Austronesian language that is an official language of Brunei, Indonesia, Malaysia, and Singapore, and that is also spo ...

it is known as ''api api putih'', ''api'' meaning "fire", referring to the fact that this mangrove attracts

fireflies The Lampyridae are a family of elateroid beetles with more than 2,000 described species, many of which are light-emitting. They are soft-bodied beetles commonly called fireflies, lightning bugs, or glowworms for their conspicuous production ...

, and ''putih'' meaning "white", referring to the pale-coloured underside of the leaves.Api-api Putih (''Avicennia alba'')
The Tide Chaser. Retrieved 2012-02-08.

Distribution and habitat

''A. alba'' is found off South and Southeast Asia, the islands of the South Pacific Ocean, and Australia. It is common in the Sungei Buloh Wetland Reserve in Singapore. It grows on tidal regions of riverbanks and on muddy portions of the seashore. It is a pioneering species, being one of the first to colonise new ground. Its widespread root system with large numbers of pneumatophores helps to stabilise new deposits of sediment.

Biology

Because it is difficult for seedlings to become established in tide-swept muddy

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

s, ''A. alba'' exhibits cryptovivipary. The

embryo An embryo is an initial stage of development of a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male spe ...

s start to develop and break through the coat of the seeds before the fruits split open to shed the seeds. In some cases, the plant also exhibits

vivipary In plants, vivipary occurs when seeds or embryos begin to develop before they detach from the parent. Plants such as some Iridaceae and Agavoideae grow cormlets in the axils of their inflorescences. These fall and in favourable circumstances the ...

, with the developing shoot breaking through the fruit capsule while it is still growing on the bush. The seedlings have hooked hairs and are often seen growing in tangled groups.

Ecology

A number of

invertebrate Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate ...

s are associated with ''A. alba''. The

larva A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. ...

e of certain small moths, '' Euopoicillia'' spp., feed on the flower buds and those of another moth, '' Autoba alabastrata'', feed on the fruits. The leaves are eaten by beetles, '' Monolepta'' spp. The greatest number of known species of

marine fungi Marine fungi are species of fungi that live in marine or estuarine environments. They are not a taxonomic group, but share a common habitat. Obligate marine fungi grow exclusively in the marine habitat while wholly or sporadically submerged in ...

are found growing in mangrove swamps where ''A. alba'' is one of a number of species colonised.Species of Higher Marine Fungi
University of Mississippi. Retrieved 2012-02-07.

Status

Mangrove habitats in general are threatened by human activities such as coastal development, agriculture, and the creation of fish ponds. Rising sea levels due to

global warming In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to E ...

will also affect mangroves communities. ''A. alba'' is affected by these threats, but the IUCN Red List of Threatened Species lists it as being of least concern because it is a fast-growing species, recovers readily from being cut, is widely distributed, and is common over much of its range.

Uses

''A. alba'' is a fast-growing species and is sometimes planted, along with ''

Sonneratia ''Sonneratia'' is a genus of plants in the family Lythraceae. Formerly the Sonneratia were placed in a family called Sonneratiaceae which included both the ''Sonneratia'' and the ''Duabanga'', but these two are now placed in their own mono ...

'' and ''

Rhizophora ''Rhizophora'' is a genus of tropical mangrove trees, sometimes collectively called true mangroves. The most notable species is the red mangrove (''Rhizophora mangle'') but some other species and a few natural hybrids are known. ''Rhizophora'' ...

'', to help prevent

coastal erosion Coastal erosion is the loss or displacement of land, or the long-term removal of sediment and rocks along the coastline due to the action of waves, currents, tides, wind-driven water, waterborne ice, or other impacts of storms. The landwa ...

. The timber from ''A. alba'' does not make good firewood or charcoal, but is used in the smoking of rubber and of fish. An extract of the

heartwood Wood is a porous and fibrous structural tissue found in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulose fibers that are strong in tension and embedded in a matrix of lignin t ...

is used in herbal medicine to make a tonic, and the

resin In polymer chemistry and materials science, resin is a solid or highly viscous substance of plant or synthetic origin that is typically convertible into polymers. Resins are usually mixtures of organic compounds. This article focuses on natu ...

has been used in birth control. The seeds are boiled and eaten as a vegetable and are sometimes available in local markets.

References

External links

* {{Taxonbar, from=Q3846890

alba ''Alba'' ( , ) is the Scottish Gaelic name for Scotland. It is also, in English language historiography, used to refer to the polity of Picts and Scottish people, Scots united in the ninth century as the Kingdom of Alba, until it developed i ...

Mangroves Afrotropical realm flora Australasian realm flora Indomalayan realm flora Oceanian realm flora Central Indo-Pacific flora Western Indo-Pacific flora Flora of tropical Asia Flora of the Caroline Islands Flora of the Northern Territory Plants described in 1826