S. alsinoides'''s distribution ranges from northern Queensland in Australia north to the island of Luzon in the Philippines and southern parts of Sulawesi in New Guinea. In Australia its typical habitat has been reported as a sandy soil in swamps that are dominated by Melaleuca quinquenervia, but has also been found on creekbanks with Melaleuca leucadendra or in some of the wetter rock crevices.
S. alsinoides's geographic range extends from northern Queensland in Australia to Luzon Island in the Philippines and southern parts of Sulawesi in New Guinea. Its preferred habitat includes sandy soil in swamps dominated by Melaleuca quinquenervia, but it has also been found on creekbanks with Melaleuca leucadendra or in wetter rock crevices.