Avicennia L. (1753) is the sole genus in the exclusively pantropic mangrove family Avicenniaceae Endl., once grouped within the family Verbenaceae. This small but widespread and distinct mangrove family is characterised by anomalous secondary thickening, leaf anatomy, characteristic pollen, incipient vivipary and seedling morphology.
Avicennia consists of eight species worldwide including: five in the Indo-West Pacific - A. alba, A. integra, A. marina, A. officinalis L. and A. rumphiana Hallier f.; and three others in the Atlantic East Pacific. Two species, A. integra and A. marina occur in Australia. Avicennia are generally considered pioneers of mangrove forests. They occupy a diversity of habitats within the tidal range and across salinity extremes of tropical and subtropical sheltered areas. In tropical regions, this often includes a select group of co-inhabitors, like Rhizophora.
In subtropical and temperate tidal habitats, Avicennia often dominant as trees or shrubs. A special cold-tolerant variety grows at latitudes as high as 38° 45’ S in southern Australia, making this the most widely distributed of any mangrove genus.
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