Family Annonaceae

Annonaceae Juss.

Including Hornschuchiaceae J.G. Agardh, Monodoraceae J.G. Agardh

Habit and leaf form. Trees, or shrubs, or lianas; bearing essential oils; resinous, or not resinous. Self supporting, or climbing; when climbing, scrambling, or stem twiners, or petiole twiners. Leaves evergreen; alternate; distichous; non-sheathing; gland-dotted, or not gland-dotted; aromatic, or without marked odour; simple. Lamina entire; pinnately veined; cross-venulate. Leaves exstipulate. Lamina margins entire. Domatia occurring in the family (in 3 genera); manifested as pockets (usually), or hair tufts (in 1/12 species).

Leaf anatomy. Abaxial epidermis papillose, or not papillose. Stomata paracytic.

Adaxial hypodermis absent. Lamina dorsiventral; with secretory cavities, or without secretory cavities. Secretory cavities containing oil, or containing mucilage, or containing resin. The mesophyll usually with spherical etherial oil cells (?); containing mucilage cells, or not containing mucilage cells; with sclerencymatous idioblasts, or without sclerenchymatous idioblasts. Main veins vertically transcurrent. Minor leaf veins without phloem transfer cells (Annona).

Stem anatomy. Secretory cavities present; with resin. Cork cambium present; initially superficial. Nodes unilacunar, or bilacunar (according to Lammers et al 1986). Primary vascular tissue centrifugal. Cortical bundles absent. Medullary bundles absent. Internal phloem absent. Secondary thickening developing from a conventional cambial ring. The secondary phloem stratified into hard (fibrous) and soft (parenchymatous) zones. ‘Included’ phloem absent. Xylem with fibre tracheids; with vessels. Vessel end-walls horizontal; simple. Vessels without vestured pits. Primary medullary rays wide, or mixed wide and narrow, or narrow. Wood diffuse porous; partially storied (VP); parenchyma apotracheal. Sieve-tube plastids P-type; type I (a). Pith with diaphragms (commonly), or without diaphragms.

Reproductive type, pollination. Plants hermaphrodite, or monoecious (rarely), or dioecious.

Inflorescence, floral, fruit and seed morphology. Flowers solitary, or aggregated in ‘inflorescences’. The ultimate inflorescence unit racemose. Flowers regular; cyclic, or partially acyclic. Sometimes the androecium acyclic (spiralled). Free hypanthium absent. Hypogynous disk present.

Perianth with distinct calyx and corolla (usually P3+3+3, with the outer one or two whorls sepaloid); usually 9; usually 3 whorled; isomerous. Calyx 3, or 6; usually 2 whorled; polysepalous; valvate, or open in bud. Corolla 3; 1–2 whorled; polypetalous; imbricate, or valvate.

Androecium usually 25–100 (i.e. ‘many’). Androecial members when many, maturing centripetally; free of the perianth; all equal; free of one another; rarely 3 whorled, or 6 whorled (otherwise spiralled). Androecium exclusively of fertile stamens (usually), or including staminodes (e.g. in Uvaria spp., where the outer members may be imperfect). Staminodes when present, external to the fertile stamens; non-petaloid. Stamens 25–100 (‘many’). Anthers adnate; non-versatile; dehiscing via longitudinal slits, or dehiscing by longitudinal valves; extrorse; tetrasporangiate; appendaged (via expansion of the connective). Endothecium developing fibrous thickenings. Microsporogenesis successive, or simultaneous. The initial microspore tetrads tetrahedral, or isobilateral, or decussate. Anther wall initially with more than one middle layer; of the ‘dicot’ type. Tapetum glandular. Pollen monosiphonous; shed in aggregates (5 genera), or shed as single grains; when aggregated, in tetrads (usually), or in polyads (octads in Trigynaea). Pollen grains aperturate (usually), or nonaperturate; 1 aperturate (mostly), or 2 aperturate; (mono) sulcate (mostly, occasionally with two parallel furrows at the equator), or ulcerate (rarely); 2-celled.

Gynoecium usually 10–100 carpelled (or more — i.e. ‘many’). The pistil when syncarpous, 1 celled, or 2–15 celled (or more?). Gynoecium apocarpous (usually), or syncarpous (rarely); eu-apocarpous (the carpels spiralled or cyclic), or synstylovarious to eu-syncarpous (e.g. Monodora); superior. Carpel 1–10 ovuled. Placentation of free carpels basal. Ovary when syncarpous 1 locular, or 2–15 locular (or more — i.e. ‘multilocular’). Stigmas wet type; papillate; Group III type. Placentation when unilocular parietal, or basal; when plurilocular basal. Ovules in the single cavity when unilocular, 1–50; 10–50 per locule (i.e. ‘many’); ascending; apotropous; with ventral raphe; arillate, or non-arillate; anatropous; bitegmic; crassinucellate. Outer integument not contributing to the micropyle. Endothelium not differentiated. Embryo-sac development Polygonum-type. Polar nuclei fusing prior to fertilization, or fusing only after one has been fertilized (?). Antipodal cells formed; 3; not proliferating; ephemeral. Synergids pear-shaped. Hypostase present, or absent. Endosperm formation cellular. Embryogeny onagrad.

Fruit fleshy; an aggregate (commonly an aggregate of berries). The fruiting carpels coalescing into a secondary syncarp, or not coalescing. The fruiting carpel indehiscent; baccate. Seeds endospermic. Endosperm ruminate (by contrast with Magnoliaceae); oily. Seeds with amyloid. Embryo achlorophyllous (4/5).

Seedling. Germination phanerocotylar, or cryptocotylar.

Physiology, biochemistry. Cyanogenic, or not cyanogenic. Alkaloids present (commonly), or absent. Iridoids not detected. Proanthocyanidins present, or absent; when present, cyanidin. Flavonols present, or absent; when present, quercetin. Ellagic acid absent (2 genera, 3 species). Arbutin absent. Sugars transported as sucrose (usually), or as oligosaccharides + sucrose (Annona squamosa). Anatomy non-C4 type (Annona).

Geography, cytology. Sub-tropical and tropical. Widespread, especially Old World. X = 7, 8, 9.

Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Magnoliiflorae; Annonales. Cronquist’s Subclass Magnoliidae; Magnoliales. APG (1998) basal order. APG 3 (2009) Order: Magnoliales.

Species 1200. Genera 126; Afroguatteria, Alphonsea, Ambavia, Anaxagorea, Ancana, Annickia, Annona, Anomianthus, Anonidium, Artabotrys, Asimina, Asteranthe, Balonga, Bocagea, Bocageopsis, Boutiquea, Cananga, Cardiopetalum, Chieniodendron, Cleistochlamys, Cleistopholis, Cremastosperma, Cyathocalyx, Cyathostemma, Cymbopetalum, Dasoclema, Dasymaschalon, Deeringothamnus, Dendrokingstonia, Dennettia, Desmopsis, Desmos, Diclinanona, Dielsiothamnus, Disepalum, Duckeanthus, Duguetia, Ellipeia, Ellipeiopsis, Enicosanthum, Ephedranthus, Exellia, Fissistigma, Fitzalania, Friesodielsia, Froesiodendron, Fusaea, Gilbertiella, Goniothalamus, Greenwayodendron, Guamia, Guatteria, Guatteriella, Guatteriopsis, Haplostichanthus, Heteropetalum, Hexalobus, Hornschuchia, Isolona, Letestudoxa, Lettowianthus, Malmea, Marsypopetalum, Meiocarpidium, Meiogyne, Melodorum, Mezzettia, Mezzettiopsis, Miliusa, Mischogyne, Mitrella, Mitrephora, Mkilua, Monanthotaxis, Monocarpia, Monocyclanthus, Monodora, Neostenanthera, Neo-uvaria, Oncodostigma, Onychopetalum, Ophrypetalum, Oreomitra,Orophea, Oxandra, Pachypodanthium, Papualthia, Petalolophus, Phaeanthus, Phoenicanthus, Piptostigma, Platymitra, Polyalthia, Polyaulax, Polyceratocarpus, Popowia, Porcelia, Pseudartabotrys, Pseudephedranthus, Pseudoxandra, Pseuduvaria, Pyramidanthe, Raimondia, Reedrollinsia, Richella, Rollinia, Ruizodendron, Sageraea, Sapranthus, Schefferomitra, Sphaerocoryne, Stelechocarpus, Stenanona, Tetrameranthus, Tetrapetalum, Toussaintia, Tridimeris, Trigynaea, Trivalvaria, Unonopsis, Uvaria, Uvariastrum, Uvariodendron, Uvariopsis, Woodiellantha, Xylopia.

Economic uses, etc. Important commercial fruits from Annona spp. (atemoya, cherimoya, custard-apple, ilarma, sugar-apple, sweet sop, sour sop), Artabotrys.

Illustrations.
• Technical details: Annona (Thonner).
• Technical details: Annona (lindley).
• Technical details: Asimena.
• Annona glabra: as A. laurifolia, Bot. Reg. 1328, 1830.

Support our developers

Buy Us A Coffee