Amaryllis and Hippeastrum plants are related and come from the tropics and sub-tropic, have large stalks and trumpet-shaped flowers. They are a genus in the amaryllidaceae family which comprises almost 100 species.
Hymenocallis
The Hymenocallis species has scented, crisp white flowers: with long spidery petals. Hymenocallis come from Central and South America.
The bulbs are now in bloom along Singapore roads.
And yes, as a reminder from Shivani, the architecture of Dubai Burj Khalifa features a triple-lobed footprint, an abstraction of the Hymenocallis flower.