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Aril Overview:
– An aril is a specialized outgrowth from a seed that covers the seed.
– Arils are edible enticements that aid in seed dispersal.
– Pseudarils are aril-like structures found on Burseraceae species.
– Some plants have false fruits formed by arils, like longan and lychee.
– Gymnosperms like yews have arils surrounding seeds instead of a pericarp layer.

– Development in Taxus:
– The fleshy aril around yew seeds is a modified seed cone scale.
– Yew arils start small, green, and turn fleshy and scarlet as they mature.
– Arils attract fruit-eating birds for seed dispersal.
– Yew seeds are toxic if consumed, except for the fleshy aril.
– Birds eat the aril and disperse the yew seeds through droppings.

– In Dacrycarpus dacrydioides:
– The kahikatea tree’s aril was a food source for Māori in New Zealand.
– Washed arils were known as “koroi” and eaten raw.

– See also:
Elaiosome: fleshy structures attached to plant seeds.
– Galbulus: fleshy cone found in junipers and cypresses.
Sarcotesta: fleshy seed coat layer, as in pomegranate.

– References:
– Banerji & Chaudhuri (1944): Study on Litchi chinensis Sonn.
– Beentje & Williamson (2010): The Kew Plant Glossary.
– Endress (1973): Research on arils in woody Ranale.
– Marshall (1992): Book on fruit and seed production.
– Ramos-Ordonez et al. (2012): Study on the fruit structure of Bursera.

Aril (Wikipedia)

An aril (pronounced /ˈærɪl/), also called an arillus, is a specialized outgrowth from a seed that partly or completely covers the seed. An arillode or false aril is sometimes distinguished: whereas an aril grows from the attachment point of the seed to the ovary (from the funiculus or hilum), an arillode forms from a different point on the seed coat. The term "aril" is sometimes applied to any fleshy appendage of the seed in flowering plants, such as the mace of the nutmeg seed. Arils and arillodes are often edible enticements that encourage animals to transport the seed, thereby assisting in seed dispersal. Pseudarils are aril-like structures commonly found on the pyrenes of Burseraceae species that develop from the mesocarp of the ovary. The fleshy, edible pericarp splits neatly in two halves, then falling away or being eaten to reveal a brightly coloured pseudaril around the black seed.

An aril that surrounds the nutmeg seed is used as a spice called mace.
The edible white aril of Litchi chinensis is sometimes called an arillode or false aril. It grows partly from the funiculus and partly from the integument of the seed.

The aril may create a fruit-like structure, called (among other names) a false fruit. False fruit are found in numerous Angiosperm taxa. The edible false fruit of the longan, lychee and ackee fruits are highly developed arils surrounding the seed rather than a pericarp layer. Such arils are also found in a few species of gymnosperms, notably the yews and related conifers such as the lleuque and the kahikatea. Instead of the woody cone typical of most gymnosperms, the reproductive structure of the yew consists of a single seed that becomes surrounded by a fleshy, cup-like covering. This covering is derived from a highly modified cone scale.

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