Which part of Litchi fruit is eaten?

A fruit's wall (pericarp) has three layers: the outer epicarp (skin), the middle mesocarp, and the inner endocarp. An aril, by contrast, is a fleshy accessory structure that develops at or near the seed's point of attachment and can grow to cover the seed independently of these wall layers.

In litchi, the rough, leathery skin that is peeled away before eating is the pericarp (fruit wall) itself, and it is discarded. The white, juicy, sweet flesh that is eaten is not a layer of this fruit wall at all: it develops as an accessory fleshy covering at or near the seed's point of attachment, so botanists classify it as a fleshy aril.

• Pericarp: this is the fruit's outer covering (rind); it is inedible and removed, not the part consumed.

• Mesocarp: in fruits such as mango, the fleshy middle layer of the wall is what gets eaten, but litchi's edible tissue does not belong to the fruit wall at all.

• Endocarp: this is the thin, hard innermost wall layer immediately around the seed; it is not fleshy, and it is not what is eaten in litchi.

Since the edible tissue develops as an accessory covering near the seed's point of attachment rather than from any pericarp layer, litchi's eaten portion is correctly termed a fleshy aril.