Appearance
It is a perennial, herbaceous liana growing to a height of 5–30 m tall with twining stems. The leaves are entire or three-lobed, 5–15 cm long, with a 5–20 cm long stem.The flowers are fragrant, white or pink, and large, 8–14 cm diameter. The flowers open quickly in the evening and last through the night, remaining open until touched by the morning sun. On overcast days, the blossoms may remain open for longer. The flowers also tend to remain open longer during cool temperatures - which may also cause the segments to snag or tear as they open.

Naming
Though formerly classified as genus "Calonyction", species "aculeatum", it is now properly assigned to genus "Ipomoea", subgenus "Quamoclit", section "Calonyction".The name moonflower derives from their blooming in the evening and their being round in shape like a full moon.
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