Anaril (/ˈærɪl/), also called anarillus, is a specialized outgrowth from aseed that partly or completely covers the seed. Anarillode orfalse aril is sometimes distinguished: whereas an aril grows from the attachment point of the seed to theovary (from thefuniculus orhilum), an arillode forms from a different point on the seed coat.^[2] The term "aril" is sometimes applied to any fleshy appendage of the seed inflowering plants, such as themace of thenutmeg seed.^[3] Arils and arillodes are often edible enticements that encourage animals to transport the seed, thereby assisting in seed dispersal.^[4]Pseudarils are aril-like structures commonly found on thepyrenes ofBurseraceae species that develop from themesocarp of the ovary.^[5] 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.

The aril may create afruit-like structure, called (among other names) afalse fruit. False fruit are found in numerousAngiosperm taxa. The edible false fruit of thelongan,lychee andackee fruits are highly developed arils surrounding the seed rather than apericarp layer. Such arils are also found in a few species ofgymnosperms, notably theyews and relatedconifers such as thelleuque and thekahikatea. Instead of thewoodycone 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.

In European yew plants (Taxus baccata), the aril starts out as a small, green band at the base of the seed, then turns brown to red as it enlarges and surrounds the seed, eventually becoming fleshy and scarlet in color at maturity. The aril is attractive to fruit-eatingbirds and is non-toxic. All other parts of the yew are toxic, including the seed housed inside the aril. If the seed is crushed, breaks or splits in the stomach of a human, bird or another animal, it will result in poisoning. Birds digest the fleshy aril as a food source, and pass the seeds out in their droppings, promotingdispersal of the seeds.

The kahikatea tree,Dacrycarpus dacrydioides, is native toNew Zealand. In pre-European times the aril of the kahikatea was a food source forMāori. The washed arils were calledkoroi and were eaten raw.^[6][7]

• Elaiosome, fleshy structures attached to the seeds of many plant species
• Galbulus, a fleshy cone borne chiefly by junipers and cypresses
• Sarcotesta, a fleshy epidermal layer of a seed coat, as in pomegranate

• Anderson, E. & Owens, J. N. (2003). Analysing the reproductive biology of Taxus: should it be included in Coniferales?Acta Hort. 615: 233–234.