Including Botryodendraceae J.G. Agardh
Habit and leaf form. Trees, or shrubs, or lianas, or herbs (rarely); bearing essential oils, or without essential oils; resinous. Perennial; with neither basal nor terminal aggregations of leaves. Self supporting, or epiphytic, or climbing; when climbing stem twiners, or root climbers. Often pachycaul. Heterophyllous (sometimes, e.g. Hedera helix, where progression from lobed to entire leaves reflects irreversible shoot maturation), or not heterophyllous. Leaves nearly always alternate (opposite only in Cheirodendron); spiral, or distichous (rarely), or four-ranked (rarely); commonly leathery; petiolate (usually), or subsessile; more or less sheathing (usually), or non-sheathing. Leaf sheaths with free margins. Leaves gland-dotted, or not gland-dotted; aromatic, or without marked odour; simple, or compound; peltate (sometimes), or not peltate; when compound, ternate, or pinnate, or palmate. Lamina when simple, dissected (usually), or entire; pinnatifid, or palmately lobed; pinnately veined, or palmately veined. Leaves stipulate, or exstipulate. Stipules when present, intrapetiolar (often adnate to and scarcely distinguishable from the base of the petiole). Vegetative buds scaly. Leaves without a persistent basal meristem; becoming compound from primordial lobes.
Leaf anatomy. Stomata present; paracytic (usually), or anomocytic. Hairs present. Complex hairs usually present; commonly stellate.
Adaxial hypodermis present (commonly), or absent. Lamina with secretory cavities. Secretory cavities containing resin. Minor leaf veins without phloem transfer cells (Aralia, Hedera).
Stem anatomy. Secretory cavities present; with resin. Cork cambium present; initially superficial. Nodes multilacunar (often), or penta-lacunar, or tri-lacunar (rarely). Cortical bundles present (commonly), or absent. Medullary bundles present, or absent. Internal phloem absent. Secondary thickening developing from a conventional cambial ring. `Included' phloem absent. Xylem without tracheids; without fibre tracheids; with libriform fibres; with vessels. Vessel end-walls simple (usually), or scalariform, or scalariform and simple. Vessels without vestured pits. Wood parenchyma paratracheal (only, often very sparse). Sieve-tube plastids S-type.
Reproductive type, pollination. Hermaphrodite, or monoecious, or andromonoecious, or gynomonoecious, or dioecious, or polygamomonoecious.
Inflorescence, floral, fruit and seed morphology. Flowers aggregated in `inflorescences'; in spikes, in heads, and in umbels. Inflorescences terminal, or axillary, or epiphyllous (rarely); umbels or heads, often massed into compound inflorescences. Flowers usually more or less 5 merous.
Perianth with distinct calyx and corolla, or petaline; (6-)10(-24); 1 whorled, or 2 whorled; isomerous, or anisomerous. Calyx when present, 3-5(-12) (sometimes reduced to small teeth); 1 whorled; when present, polysepalous; entire, or lobulate, or lobed, or toothed; often open in bud. Corolla (3-)5(-12); 1 whorled; polypetalous, or gamopetalous (rarely connate at the base or forming a calyptra); calyptrate (rarely), or not calyptrate; imbricate, or valvate; regular.
Androecium (3-)5(-12), or 10-100 (the same number as the corolla members, twice the number, or `many'). Androecial members free of the perianth; free of one another. Stamens (3-)5(-12), or 10-100; isomerous with the perianth, or diplostemonous, or polystemonous. Anthers dehiscing via longitudinal slits; tetrasporangiate. Endothecium developing fibrous thickenings. Microsporogenesis simultaneous. The initial microspore tetrads tetrahedral, or isobilateral. Anther wall initially with one middle layer, or initially with more than one middle layer. Tapetum glandular. Pollen grains aperturate; 3 - aperturate (mostly), or 2 - aperturate, or 4 - aperturate, or 6 - aperturate; colporate (mostly), or colpate, or rugate; 3-celled.
Gynoecium 2-5(-100) (i.e., sometimes `many'); syncarpous; synovarious; inferior, or superior (rarely). Ovary 1-200 locular. Epigynous disk present. Styles free, or partially joined. Stigmas wet type, or dry type; papillate; Group II type and Group III type. Placentation apical. Ovules 1(-2) per locule; pendulous; epitropous; anatropous; unitegmic; usually crassinucellate, or tenuinucellate. Endothelium differentiated. Polar nuclei fusing prior to fertilization. Antipodal cells formed, or not formed (then the three nuclei degenerating early); when formed, 3; not proliferating. Synergids pear-shaped. Hypostase present, or absent. Endosperm formation nuclear.
Fruit fleshy, or non-fleshy; indehiscent, or a schizocarp; when schizocarpic, comprising mericarps; (when non-schizocarpic) a berry, or a drupe (with as many pyrenes as locules). Fruits from adjoining flowers aggregated into compound fruits, or not aggregated into compound fruits. Seeds endospermic. Endosperm oily. Cotyledons 2. Embryo achlorophyllous (2/3).
Seedling. Germination phanerocotylar.
Physiology, biochemistry. Not cyanogenic. Polyacetylenes recorded (falcarinone). Alkaloids present, or absent. Iridoids absent (discounting a record for Hedera: Jensen et al. 1975). Proanthocyanidins absent. Flavonols present, or absent; quercetin, or kaempferol and quercetin. Ellagic acid absent (5 species, 5 genera). Arbutin absent. Saponins/sapogenins present. Aluminium accumulation not found. Inulin not found (umbelliferose recorded). C3. C3 recorded in Hedera.
Geography, cytology. Temperate (a few), or sub-tropical to tropical (mainly). Widespread, but especially Indomalaya and tropical America. X = 11, 12(+).
Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgren's Superorder Araliiflorae; Araliales. Cronquist's Subclass Rosidae; Apiales. Takhtajan's Subclass Rosidae; Aralianae; Araliales. Species 700. Genera 49; Anakasia, Apiopetalum, Aralia, Arthrophyllum, Astrotricha, Boninofatsia, Brassaiopsis, Cephalaralia, Cheirodendron, Cromapanax, Cuphocarpus, Cussonia, Delarbrea, Dendropanax, Eleutherococcus, Fatsia, Gamblea, Gastonia, Harmsiopanax, Hedera, Heteropanax, Hunaniopanax, Kalopanax, Mackinlaya, Macropanax, Megalopanax, Merrilliopanax, Meryta, Motherwellia, Munroiodendron, Myodocarpus, Oplopanax, Oreopanax, Osmoxylon, Panax, Pentapanax, Polyscias, Pseudopanax, Pseudosciadium, Reynoldsia, Schefflera, Sciadodendrom, Seemannaralia, Sinopanax, Stilbocarpa, Tetrapanax, Tetraplasandra, Trevesia, Woodburnia.
Economic uses, etc. Some cultivated ornamentals, including notable houseplants, e.g. Hedera, Aralia, Polyscias, Schefflera, Fatsia. Ginseng roots from Panax quinquefolius, Chinese rice paper from the pith of Tetrapanax papyriferus.
Illustrations. arali401.gif arali472.gif arali780.gif arali471.gif
Additional, to be intercalated. Flowers calyptrate (rarely), or not calyptrate.
