What is the Difference Between Achene and Cypsela?

The main difference between an achene and a cypsela lies in their origin and structure. Both are simple, dry, and indehiscent fruits containing a single seed, but they have distinct characteristics:

1. Origin: An achene develops from a single carpel and a superior ovary, while a cypsela originates from two carpels and an inferior ovary.
2. Pappus: Achenes do not have a pappus, which is a structure made of hairs or bristles, while cypselas may contain a pappus.
3. Perianth: According to Spjut (1994), cypselae differ from achenes by the presence of an extra layer derived from the perianth and formed over the pericarp as a result of the inferior position of the ovary.

For example, the fruits of the buttercup family and the sunflower family are considered achenes because they develop from a single carpel and a superior ovary. In contrast, the fruits of the Asteraceae family, such as dandelions, are considered cypselas because they originate from two carpels and an inferior ovary and may have a pappus.

Comparative Table: Achene vs Cypsela

Here is a table comparing the differences between an achene and a cypsela:

Some key differences between achenes and cypselae include:

• Achenes originate from a superior ovary, while cypselae originate from an inferior ovary.
• Achenes do not have a pappus (a modified calyx) attached, whereas cypselae may contain a pappus.
• Examples of achenes include fruits from the buttercup family, sunflower family, rose family, and strawberry, while examples of cypselae include fruits from the dandelion and daisy family.