Achenaceous

Achenaceous is a botanical term used to describe plants whose fruits are achenes, or plants that bear achenes as their primary dry fruit. An achene is a small, dry, indehiscent fruit that contains a single seed and does not split open at maturity.

In an achene, the seed is enclosed by a thin pericarp that is not fused to the seed coat. The fruit is typically dispersed by wind, water, or animals, and may bear structures such as a pappus in some species to aid dispersal, as seen in dandelions.

Achenaceous fruits are common in the Asteraceae family, where each floret can form an individual achene, and in several other plant groups. Notable examples include the achenes produced by sunflowers and dandelions. In strawberry, the small yellow structures on the surface are true achenes, while the red flesh is an accessory fruit.

The term is used in botanical descriptions to distinguish this simple, dry fruit type from others such as nuts, capsules, or berries. The word derives from achene, reflecting the single-seeded nature of these fruits.