Caryopsis

caryopses) is a type of simple fruit—one that is monocarpellate (formed from a single carpel) and indehiscent (not opening at maturity) [1] and resembles an achene, except that in a caryopsis the pericarp is fused with the thin seed coat.The caryopsis is popularly called a grain and is the fruit typical of the family Poaceae (or Gramineae), which includes wheat, rice, and maize.The name caryopsis is derived from the Greek words karyon and -opsis (κάρυον and ὄψις), meaning 'nut' and 'having the appearance of', respectively.The term was first used by Achille Richard to refer to the dry, monospermic, indehiscent fruit commonly found in grasses.The other forms of fruit proposed to be borne by grasses include achenes,[4] utricles,[4] berries,[5] and nuts.
An assortment of different caryopses.
Wheat spikelet with the three anthers sticking out.
Caryopsis cross-section.
botanycarpelindehiscentachenepericarpPoaceaecerealdry fruitbractsAchille RichardachenesutriclesberriesCrypsisEleusineDinochloaOlmecaDendrocalamusSchizostachyumRichard, Louis-ClaudeCharles-François Brisseau de MirbelfruitsHesperidiumCapsuleFollicleLegumeLomentSamaraSchizocarpSiliqueSyconiumAccessory fruitCompound fruitAggregate fruitMultiple fruitDehiscent fruitDiasporeDrift fruit