Unlike simple fruits, which develop from a single ovary in a flower, an etaerio develops from multiple ovaries (sometimes called fruitlets) in a single flower arranged over the surface of or within the flower’s receptacle. An etaerio is also called an aggregate fruit. Fruits like achenes, samaras, follicles, berries, and drupes can be simple or aggregated, depending on the plant species.
Etaerio of achenes (an aggregate of one-seeded, dry, indehiscent fruits)
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Etaerio of samaras (an aggregate of winged achenes)
Etaerio of follicles (an aggregate of dry, dehiscent, unilocular [containing a single cavity] fruits with two or more seeds formed from a single carpel)
Etaerio of berries (an aggregate of fleshy berries crowded on the receptacle)
Etaerio of drupes (an aggregate of fleshy drupes or drupelets)