''Avicennia alba'' is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

of tropical

mangrove A mangrove is a shrub or tree that grows mainly in coastal saline water, saline or brackish water. Mangroves grow in an equatorial climate, typically along coastlines and tidal rivers. They have particular adaptations to take in extra oxygen a ...

in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Acanthaceae Acanthaceae () is a Family (biology), family (the acanthus family) of dicotyledonous flowering plants containing almost 250 genera and about 2500 species. Most are Tropics, tropical Herbaceous plant, herbs, shrubs, or twining vines; some are epip ...

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

vascular system In vertebrates, the circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the body. It includes the cardiovascular system, or vascular system, that consists of the heart a ...

. 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 ( , ; , Jawi alphabet, Jawi: ) is an Austronesian languages, Austronesian language spoken primarily by Malays (ethnic group), Malays in several islands of Maritime Southeast Asia and the Malay Peninsula on the mainland Asia. The lang ...

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, habitat refers to the array of resources, 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 manifestation of its ...

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

embryo An embryo ( ) is the initial stage of development for 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 sp ...

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 t ...

, 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 animals that neither develop nor retain a vertebral column (commonly known as a ''spine'' or ''backbone''), which evolved from the notochord. It is a paraphyletic grouping including all animals excluding the chordata, chordate s ...

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

larva A larva (; : larvae ) is a distinct juvenile form many animals undergo before metamorphosis into their next life stage. Animals with indirect development such as insects, some arachnids, amphibians, or cnidarians typically have a larval phase ...

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 are found growing in mangrove swamps where ''A. alba'' is one of a number of species colonised.

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 Present-day climate change includes both global warming—the ongoing increase in global average temperature—and its wider effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes ...

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 monotyp ...

'' and '' 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 Wind wave, waves, Ocean current, currents, tides, wind-driven water, waterborne ice, or other impacts ...

. 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 structural tissue/material found as xylem in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulosic fibers that are strong in tension and embedded in a matrix of lignin t ...

is used in

herbal medicine Herbal medicine (also called herbalism, phytomedicine or phytotherapy) is the study of pharmacognosy and the use of medicinal plants, which are a basis of traditional medicine. Scientific evidence for the effectiveness of many herbal treatments ...

to make a tonic, and the

resin A resin is a solid or highly viscous liquid that can be converted into a polymer. Resins may be biological or synthetic in origin, but are typically harvested from plants. Resins are mixtures of organic compounds, predominantly terpenes. Commo ...

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 Scots united in the ninth century as the Kingdom of Alba, until it developed into the Kingd ...

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