Trees, shrubs, or climbers, wood and leaves often aromatic; indument of simple or less often (Uvaria, Annona) stellate hairs. Leaves alternate, normally distichous. Stipules absent. Petiole usually short; leaf blade simple, venation pinnate, margin entire. Inflorescences terminal, axillary, leaf-opposed, or extra-axillary [rarely on often underground suckerlike shoots]. Flowers usually bisexual, less often unisexual, solitary, in fascicles, glomerules, panicles, or cymes, sometimes on older wood, usually bracteate and/or bracteolate. Sepals hypogynous, [2 or]3, imbricate or valvate, persistent or deciduous, rarely enlarging and enclosing fruit, free or basally connate. Petals hypogynous, 3-6(-12), most often in 2 whorls of 3 or in 1 whorl of 3 or 4[or 6], imbricate or valvate, sometimes outer whorl valvate and inner slightly imbricate. Stamens hypogynous, usually many, rarely few, spirally imbricate, in several series; filaments very short and thick; anther locules 2, contiguous or separate, rarely transversely locular, adnate to connective, extrorse or lateral, very rarely introrse, opening by a longitudinal slit; connectives often apically enlarged, usually ± truncate, often overtopping anther locules, rarely elongated or not produced. Carpels few to many, rarely solitary, free or less often connate into a 1-locular ovary with parietal placentas; ovules 1 or 2 inserted at base of carpel or 1 to several in 1 or 2 ranks along ventral suture, anatropous; styles short, thick, free or rarely connate; stigmas capitate to oblong, sometimes sulcate or 2-lobed. Fruit usually apocarpous with 1 to many free monocarps, these sometimes moniliform (constricted between seeds when more than 1-seeded), often fleshy, indehiscent, rarely dehiscent (Anaxagorea, Xylopia), and often with base extended into stipe, rarely on slender carpophore (Disepalum), less often syncarpous with carpels completely connate and seeds irregularly arranged and sometimes embedded in fleshy pulp. Seeds 1 to many per monocarp or many per syncarp, often arillate; endosperm copious, ruminate; embryo minute, near hilum.
Trees, shrubs, rarely woody vines, deciduous or evergreen, with aromatic bark, leaves, and flowers. Pith septate to diaphragmed. Leaves alternate, simple, without stipules, petiolate. Leaf blade pinnately veined, unlobed, margins entire. Inflorescences axillary to leaf scars on old wood or to leaves on new shoots, solitary flowers or few-flowered fascicles, pedunculate; bracts or bracteoles present or absent. Flowers bisexual, rarely unisexual; receptacle becoming enlarged, elevated or flat; perianth hypogynous, segments valvate or imbricate; sepals persistent, (2-)3(-4), distinct or basally connate; petals either 6 in 2 unequal whorls of 3 with petals of outer whorl larger, petals of inner whorl fleshier than the outer, often with corrugate nectary zone, or petals 6-12(-15), nearly equal or unequal, veins impressed on inner face; stamens 10-20 or very numerous, hypogynous, spirally arranged, forming ball or flat-topped mass; filament short, stout; anther linear to oblong-linear, extrorse, longitudinally dehiscent; connective apically elongate, connivent; pistils 1-many, superior, 1-carpellate, 1-locular, distinct or connate to various degrees with at least stigmas distinct; placentation marginal, placenta 1; ovules 1-many per pistil; style short, thick; stigma terminal. Fruits berries, distinct, 1-8(-12) per flower, or coalescent, forming syncarps, 1 per flower. Seeds 1-many per pistil, arillate; endosperm ruminate, oily.
Petals generally 6, in two series, valvate or slightly imbricate, rarely in two series of 2, or the inner series absent
Flowers terminal, leaf-opposed or axillary, solitary or crowded, hermaphrodite or rarely unisexual, mostly trimerous
Sepals 3, rarely 2, separate or united into a 3-lobed calyx, valvate or rarely imbricate, persistent or deciduous
Seed with or without an aril, with copious ruminate endosperm and minute embryo
Fruiting carpels sessile or stipitate, mostly indehiscent
Carpels numerous or rarely few or solitary, free or very rarely united into a 1-celled ovary with parietal placentas; ovules 1 or more
Stamens generally numerous, hypogynous; anther-cells adnate, with the connective often truncate
Fries, R. E. 1931. Revision der Arten einiger Annonaceen-Gattungen. Acta Horti Berg. 10: 1-341. Fries, R. E. 1934. Revision der Arten einiger Annonaceen-Gattungen. Acta Horti Berg. 12(1): 1-220. Fries, R. E. 1939. Revision der Arten einiger Annonaceen-Gattungen. Acta Horti Berg. 12(3): 289-577. Hutchinson, J. 1923. Contributions toward a phylogenetic classification of flowering plants. II. The genera of Annonaceae. Bull. Misc. Inform. Kew: 241-261. Kral, R. 1960. A revision of Asimina and Deeringothamnus (Annonaceae). Brittonia 12(4): 233-278. Rusby, H. H. 1935. The custard-apple family in Florida. J. New York Bot. Gard. 36: 233-239.