Habitat
This organism is a cyanobacteria that forms colonies in tropical and subtropical water bodies. These water bodies could be characterized by high levels of carbonate and bicarbonate.
Arthrospira platensis thrives in alkaline marine environments with a pH of up to 11. Because of this extremely salty environment, there aren't many other organisms that can co-exist with A. platensis.
As you can see in the world map below, A. platensis grows mostly in Africa. It is also known to grow in parts of Asia and South America. Primitive societies were found to have discovered spirulina and its medicinal properties. They harvested the spirulina and made it into dried patties so that they could more easily digest it.
Some other organisms that live in this same habitat are the sweet oranges, castor beans, ants, hibiscus plants, apple guava, papaya, and curare.
It's important to understand how A. platensis adapts to its environment!