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The Annonaceae are a family, the custard apple family, of flowering plants consisting of trees, shrubs, or rarely lianas.〔 With 2106 accepted species and more than 130 genera, it is the largest family in Magnoliales. Several genera produce edible fruit, most notably ''Annona'', ''Anonidium'', ''Asimina'', ''Rollinia'', and ''Uvaria''. Its type genus is ''Annona''. The family is concentrated in the tropics, with few species found in temperate regions. About 900 species are Neotropical, 450 are Afrotropical, and the other species Indomalayan. Compared to the species from the Neotropics, very little is known about many species from Indomalaya. Only a few attempts have been made for the phylogeny-based reclassification of the family, and those have been hampered by the Neotropic bias in the available information, with the most of the work having been done on genera and tribes. ==Description== Mostly tropical, some mid-latitude, deciduous or evergreen trees and shrubs, some lianas, with aromatic bark, leaves, and flowers.〔 ; Stems, stalks and leaves: Bark is fibrous and aromatic. Pith septate (fine tangential bands〔 divided by partitions) to diaphragmed (divided by thin partitions with openings in them).〔 : Branching distichous (arranged in two rows/on one plane) or spiral.〔 : Leaves are alternate, two-ranked,〔 〕 simple, pinnately veined, and have leaf stalks. Stipules absent.〔 ; Flowers: Flower stalks are axillary to (on the opposite side of shoot from) leaf scars on old wood and sometimes from leaves on new shoots. The flowers are usually trimerous; borne singly or in compound inflorescences; bisexual and rarely unisexual. The receptacle might become enlarged, elevated or flat. The outer whorls are inserted below the ovaries, and have valvate (overlapping) or imbricate (nonoverlapping) segments. Usually two to four persistent sepals that are distinct or connate (fused) at the base. Six petals in two unequal whorls of three with larger outer whorls and fleshier inner whorls that might share the same nectar glands, or six to fifteen petals, with impressed veins on their inner face. Ten to twenty (or many more) stamens inserted below the ovary, spirally arranged and forming a ball or flat-topped mass with short and stout filaments and linear to oblong anthers which face outward and open longitudinally. Each flower can have from one to many pistils, distinct to connate, with stigmas distinct. Marginal placentation, each pistil bearing one locule, with one to many ovules. Style short and thick, with terminal stigma.〔 ; Fruits and seeds: Fruits are single berries or coalesce from several pistils (into aggregate fruit, syncarps). Seeds are one to many per pistil; have a fleshy and usually brightly colored cover, have ruminate endosperm (nutritive tissue surrounding the embryo) and are oily.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Annonaceae」の詳細全文を読む スポンサード リンク
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