Which plant is recognized as the smallest of all flowering plants?

The smallest of all flowering plants is Wolffia spp, commonly referred to as watermeal. This plant is known for its incredibly minute size, often measuring less than one millimeter in diameter. Wolffia spp are floating aquatic plants found in freshwater ecosystems, and they lack true roots, which contributes to their diminutive dimensions. Their small size allows them to thrive in a variety of aquatic environments, often forming dense mats on the surface of slow-moving waters.

In contrast, other options represent different types of aquatic plants with larger structures. For instance, Lemna minor, also known as duckweed, is small but typically larger than Wolffia spp. Nymphaea odorata, or the American white water lily, is a much larger plant, characterized by its broad leaves and beautiful flowers. Ceratophyllum demersum, or coontail, is a submerged aquatic plant that can grow several feet long, featuring a distinct and larger structure compared to Wolffia spp. Therefore, recognizing Wolffia spp as the smallest flowering plant is anchored in its unique morphological characteristics and ecological adaptations.