They are difficult to tell apart except when there are flowers on the tree. These trees grow to 15 m tall. Thick, tall peg type above-ground roots. Leaves are about 7 cm long, rounded and opposite each other on the branches. The tips of the leaves are slightly turned under.
Flowers only open for one night.
Grey to brown bark that is slightly cracked. These trees can tolerate a wide salinity range. S. alba generally occurs lower in the intertidal zone than S. caseolaris , and is often associated with the Grey and Red Mangroves. The distribution of S. alba is shown on the map opposite. S. caseolaris can be found as far south as Hinchinbrook Island.