The families of flowering plants
Including Atriplicaceae Juss., Corispermaceae Link, Farinaceae Dulac, Salicornieae (Salicorniaceae) J.G. Agardh, Salsolaceae Moq.-Tandon; excluding Dysphaniaceae, Halophytaceae, Sarcobataceae.
Habit and leaf form. Herbs (mostly halophytic), or shrubs (some), or trees (few, small), or lianas (few). Normal plants and switch-plants; sometimes more or less cactoid, with succulent, photosynthetic stems (e.g. Salicornia). Leaves well developed, or much reduced, or absent. Plants succulent, or non-succulent. Annual, or biennial, or perennial (often glaucous); with a basal aggregation of leaves, or without conspicuous aggregations of leaves. Self supporting (usually), or climbing (few). Helophytic to xerophytic (nearly all halophytic). Leaves minute to large; alternate, or opposite; when alternate, spiral, or distichous (rarely); herbaceous, or fleshy, or membranous; petiolate to sessile; when opposite, connate (not uncommonly, e.g. represented by lobed cupules at the internodes of succulent stems), or not connate; sheathing, or non-sheathing; simple; epulvinate. Lamina dissected, or entire; one-veined (?), or pinnately veined; hastate, or sagittate, or attenuate at the base, or cuneate at the base. Leaves exstipulate; leaf development not graminaceous.
General anatomy. Plants with crystal sand, or without crystal sand.
Leaf anatomy. The leaf lamina when not much reduced, dorsiventral (rather uncommonly), or bifacial to centric. Hydathodes present (sometimes), or absent. Stomata universally on both surfaces (or in all parts of the epidermes); anomocytic (usually), or paracytic (in a few species and genera). Hairs of numerous kinds present (see illustration); eglandular and glandular; mostly multicellular. Multicellular hairs uniseriate (eclusively?); branched and simple (commonly 2-armed, sometimes candelabra type). Complex hairs present, or absent; sometimes stellate. Adaxial hypodermis present, or absent. The mesophyll containing crystals. The crystals mainly druses (and sand). Minor leaf veins without phloem transfer cells (6 genera).
Axial (stem, wood) anatomy. Cork cambium present, or absent; when present, initially deep-seated, or initially superficial. Nodes unilacunar. Primary vascular tissues comprising a ring of bundles; collateral (?). Internal phloem absent. Cortical bundles absent. Medullary bundles present, or absent (ostensibly common, but supposedly representing leaf traces laid down before the onset of secondary thickening), or absent. Secondary thickening developing from a conventional cambial ring (rarely?), or anomalous (nearly always). The anomalous secondary thickening usually via concentric cambia (these comprising rings or arcs, generating numerous vascular bundles in spirals, in rings or distributed irregularly).
The wood semi-ring porous (occasionally), or diffuse porous. The vessels small (sometimes extremely so); in radial multiples, or clustered, or in tangential arcs (typically in groups or clusters internal to the phloem strands). The vessel end-walls simple. The vessels with spiral thickening (commonly), or without spiral thickening. The axial xylem with tracheids, or without tracheids; without fibre tracheids; with libriform fibres; without septate fibres. The fibres without spiral thickening. The parenchyma paratracheal (and conjunctive). Included phloem present (very commonly, typically of the concentric type but occasionally foraminate), or absent. The wood not storied (VP, in all those with secondary growth).
Reproductive type, pollination. Plants hermaphrodite (usually), or monoecious (sometimes), or andromonoecious (rarely), or gynomonoecious, or dioecious (rarely), or polygamomonoecious.
Inflorescence, floral, fruit and seed morphology. Flowers solitary (then axillary), or aggregated in inflorescences (or sometimes paired); when solitary or paired, axillary; when flowers aggregated, in cymes (the cymes mostly in racemose arrangements). The ultimate inflorescence units cymose. Inflorescences terminal, or axillary; mostly racemes of cymes. Flowers minute, or small; regular; cyclic; when hermaphrodite, usually tricyclic (sometimes 2-cyclic). Free hypanthium present (the stamens then inserted on a disk on the calyx), or absent. Hypogynous disk often present (but not always?).
Perianth sepaline, or vestigial to absent; (1–)5(–6); joined (imbricate); 1 whorled; fleshy, or non-fleshy; persistent; accrescent, or non-accrescent. Calyx (interpreting the perianth as such) (1–)3–5(–6); gamosepalous (nearly always), or polysepalous (in Salsola?); commonly becoming appendaged with spines, tubercles or wings; fleshy (commonly), or non-fleshy (then usually herbaceous or membranous); persistent (in the fruit); accrescent (usually, enclosing the fruit and often appendaged with wings, tubercles or spines), or non-accrescent; imbricate.
Androecium 3–5. Androecial members free of the perianth, or adnate (to the base of the perianth); all equal (by contrast with most Amaranthaceae); free of one another (usually, by contrast with most Amaranthaceae), or coherent; when coherent 1 adelphous (connate at the base); 1 whorled. Androecium nearly always exclusively of fertile stamens (by contrast with many Amaranthaceae). Stamens 3–5; usually isomerous with the perianth; oppositisepalous (when ascertainable). Anthers bent inwards in bud; dehiscing via longitudinal slits; tetrasporangiate. Endothecium developing fibrous thickenings. Microsporogenesis simultaneous. The initial microspore tetrads tetrahedral, or isobilateral, or decussate. Anther wall initially with one middle layer, or initially with more than one middle layer; of the monocot type. Tapetum glandular (usually), or amoeboid. Pollen grains aperturate; 8–90 aperturate; (oligo-to poly-) foraminate; spinulose; 3-celled (7 genera).
Gynoecium (2–)5 carpelled. The pistil 1 celled. Gynoecium syncarpous; synovarious to synstylovarious; superior (usually), or partly inferior (rarely). Ovary 1 locular. Styles (1–)2–3(–4); usually partially joined. Stigmas dry type; papillate; Group II type. Placentation basal. Ovules in the single cavity 1; pendulous, or ascending; non-arillate; campylotropous; bitegmic; crassinucellate. Outer integument not contributing to the micropyle. Embryo-sac development Polygonum-type. Polar nuclei usually fusing prior to fertilization. Antipodal cells formed; 3; proliferating (a little, e.g. Beta vulgaris), or not proliferating (usually); usually ephemeral. Synergids pear-shaped, or hooked. Endosperm formation nuclear. Endosperm haustoria present, or absent; when developed, chalazal. Embryogeny chenopodiad.
Fruit non-fleshy; indehiscent, or dehiscent; a nut (usually), or capsular-indehiscent (commonly a utricle); enclosed in the fleshy hypanthium, or enclosed in the fleshy perianth (commonly), or without fleshy investment external to the original ovary. Gynoecia of adjoining flowers combining to form a multiple fruit, or not forming a multiple fruit. Seeds more or less non-endospermic. Perisperm present, or absent (the variation of classificatory interest). Seeds with starch. Cotyledons 2. Embryo chlorophyllous (5/11), or achlorophyllous (3/5 (Atriplex, Chenopodium, Beta)); coiled (usually), or curved, or bent.
Seedling. Germination phanerocotylar.
Physiology, phytochemistry. C3, or C4. C3 physiology recorded directly in Agriophyllum, Allenrolfia, Anthochlamys, Arthrocnemum, Atriplex, Bassia, Beta, Blitum, Ceratocarpus, Chenopodium, Eurotia, Halimione, Halisarcia, Halocnemum, Halosarcia, Haplopeplis, Halostachya, Kalidium, Micronemum, Pachycornia, Salicornia, Salsola, Sclerostegia, Spinacia, Suaeda, Tecticornia. C4 physiology recorded directly in Aellinia, Agathophora, Anabasis, Arthrophytum, Atriplex, Bassia, Camphorosma, Climacoptera, Cornulaca, Gamanthus, Girgensohnia, Halanthium, Halarchon, Halimocnemis, Halocharis, Halogeton, Halosarcia, Halotis, Haloxylon, Hammada, Horaninovia, Hypocyclix, Kochia, Noaea, Panderia, Petrosimonia, Salsola, Suaeda, Theleophyton, Traganum. Anatomy C4 type (Aellenia, Anabasis, Arthrophytum, Atriplex (see illustration), Bassia (see illustration), Camphorosma, Chenolea, Girgensohnia, Halanthium, Halosarcia, Kochia, Panderia, Petrosimonia, Salsola, Suaeda, etc.), or non-C4 type (Allenrolfea, Arthrocnemum, Atriplex, Bassia, Ceratocarpus, Chenolea, Chenopodium, Halimione, Halocnemum, Halopeplis, Halosarcia, Kochia, Maireana, Pachycornia, Salicornia, Salsola (see illustration), Sarcocornia, Sclerostegia, Suaeda, Tecticornia etc.). Inulin recorded (? Beta). Cyanogenic, or not cyanogenic. Alkaloids present, or absent. Anthraquinones detected (Salsola); polyacetate derived. Arbutin absent. Iridoids not detected. Betalains present. Saponins/sapogenins present, or absent. Proanthocyanidins absent. Flavonols present; kaempferol, or kaempferol and quercetin. Ellagic acid absent (7 species, 7 genera). Aluminium accumulation not found. Plants often accumulating free oxalates. Sieve-tube plastids P-type; type III (c).
Geography, cytology. Temperate to sub-tropical. Widespread, but missing from Central America, Asia, Malaysia and most of Africa. X = (6)9.
Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgrens Superorder Caryophylliflorae; Caryophyllales. Cronquists Subclass Caryophyllidae; Caryophyllales. APG 3 core angiosperms; core eudicot; Superorder Caryophyllanae; Order Caryophyllales (under Amaranthaceae!).
Species 1400. Genera about 105; Acroglochin, Aellenia (= Halothamnus), Agathophora, Agriophyllum, Alexandra, Allenrolfea, Anabasis, Anthochlamys, Aphanisma, Archiatriplex, Arthocnemum, Arthrophytum, Atriplex, Axyris, Baolia, Bassia, Beta, Bienertia, Blitum, Borsczowia, Camphorosma, Ceratocarpus, Chenopodium, Climacoptera, Corispermum, Cornulaca, Cremnophyton, Cyathobasis, Cycloloma, Didymanthus, Dissocarpus, Einadia, Enchylaena, Eremophea, Eriochiton, Exomis, Fadenia, Fredolia, Gamanthus, Girgensohnia, Grayia, Hablitzea, Halanthium, Halarchon, Halimione, Halimocnemis, Halocharis, Halocnemum, Halogeton, Halopeplis, Halosarcia, Halostachys, Halothamnus, Haloxylon, Hammada, Hemichroa (~ Amaranthaceae), Heterostachys, Holmbergia, Horaninovia, Iljinia, Kalidium, Kirilowia, Kochia, Krascheninnikovia, Lagenantha, Maireana, Malacocera, Manochlamys, Microcnemum, Microgynoecium, Monolepis, Nanophyton, Neobassia, Nitrophila, Noaea, Nucularia, Ofaiston, Oreobliton, Osteocarpum, Pachycornia, Panderia, Petrosimonia, Physandra, Piptoptera, Polycnemum, Rhagodia, Raphidophyton, Roycea, Salicornia, Salsola, Sarcocornia, Scleroblitum, Sclerochlamys, Sclerolaena, Sclerostegia, Seidlitzia, Sevada, Spinacia, Stelligera, Suaeda, Suckleya, Sympegma, Tecticornia, Tegicornia, Teloxys, Threlkeldia, Traganopsis, Traganum, Zuckia.
General remarks. Comparison of this description with that of Amaranthaceae (q.v.) shows markedly differing tendencies in some overlapping characters, especially in habitat preferences and in details of the androecium (equal, free stamens and no staminodes in most chenopods); but there seem to be no convincing absolute differences, and it seems legitimate to regard the chenopods as mainly halophytic Amaranthaceae.
Economic uses, etc. Contributes sugarbeet and Swiss chard (Beta vulgaris), spinach (Spinacia oleracea), and saltbush pastures.
Illustrations. • Technical details: Chenopodium, Beta. • Technical details: Salicornia, Salsola (Lindley). • Technical details: Traganum (Thonner). • Atriplex hastata (as A. deltoidea) and A. glabriuscula (as A. babingtonii): Eng. Bot. 1204 and 1206, 1868. • Atriplex billardierei: Hooker, Fl. Tasmaniae (1860). • Chenopodium glaucum and Chenopodium bonus-henricus: Eng. Bot. 1198 and 1199, 1868. • Chenopodium vulvaria and Chenopodium rubrum: Eng. Bot. 1187 and 1196, 1868. • Madhuca microphylla, as Bassia: Hook. Ic. Pl. 1 (1837). • C3 anatomy: Atriplex hastata, fluorescent-labelled Rubisco: Hattersley et al., 1977. • C4 anatomy: Atriplex rosea, fluorescent-labelled Rubisco: Hattersley et al., 1977. • Beta vulgaris ssp. maritima (as B. maritima): Eng. Bot. 1184, 1868. • Salicornia europaea (as S. herbacea) and S. perennis (as S. radicans): Eng. Bot. 1181 and 1183, 1868. • Salsola kali: Eng. Bot. 1180, 1868. • C4 anatomy: Salsola kali, fluorescent-labelled Rubisco: Hattersley et al., 1977. • Suaeda fruticosa and Suaeda maritima: Eng. Bot. 1178 and 1179, 1868. • Chenopodium, Salsola: B. Ent. compilation, 1824–35. • Salicornia, Halimione, Atriplex: B. Ent. compilation, 1824–35. • Atriplex, Axyris, Chenopodium, Corispermum, Eurotia, Grayia, Kirilowia, Petrosimonia: leaf hairs (Solereder, 1908). • Atriplex, Bassia, Salsola: transverse leaf sections (Solereder, 1908).
We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, distributions of character states within any set of taxa, geographical distribution, genera included in each family, and classifications (Dahlgren; Dahlgren, Clifford, and Yeo; Cronquist; APG). See also Guidelines for using data taken from Web publications.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 1992 onwards. The families of flowering plants: descriptions, illustrations, identification, and information retrieval. Version: 13th March 2017. delta-intkey.com/angio’.