| The Families of Angiosperms |
L. Watson and M.J.Dallwitz
IncludingDeeringiaceae J.G. Agardh,Subscariosaceae Dulac;excludingChenopodiaceae,Goetzeaceae
Habit and leaf form.Shrubs andherbs.Plants succulent (occasionally, if the halophyticHemichroais referred here rather than toChenopodiaceae), or non-succulent(mostly);green and photosynthesizing. With a basal aggregation of leaves(occasionally, e.g. inPtilotus), or without conspicuous aggregations ofleaves (usually). Self supporting, or climbing (occasionally). Leaves alternate,or opposite; ‘herbaceous’ (mostly), or fleshy (perhaps onlyHemichroa); sheathing, or non-sheathing; simple. Lamina entire;one-veined, or pinnately veined.Leavesexstipulate. Laminamargins entire. Domatia commonly occurring in the family.
General anatomy.Plants commonlywith ‘crystal sand’.
Leaf anatomy.The leaflamina dorsiventral (very rarely tending to isobilateral). Abaxial epidermisnot papillose. Stomata on both surfaces (commonly), or mainly confined to onesurface (usually more numerous abaxially); anomocytic, or anisocytic (? -subsidiary patterns not precisely specified by Solereder or Metcalfe and Chalk).Hairs present (of assorted types, see illustration; but only uniseriatetrichomes that often form dense woolly or silky indumentum seem to predominateacross the family); eglandular and glandular; mostly seemingly multicellular.Multicellular hairs branched and simple. Complex hairs present, or absent;sometimes stellate, or capitate. Adaxial hypodermis absent. The mesophyllcontaining crystals. The crystals mostly druses (and crystal sand, solitarytypes being rare; cf.Caryophyllaceae, differing fromNyctaginaceae in absence of raphides and styloids). Main veins embedded.Minor leaf veins without phloem transfer cells (Amaranthus,Celosia).
Axial (stem, wood) anatomy.Corkcambium present, or absent; initially superficial. Nodes unilacunar. Primaryvascular tissues presumably comprising a ring of bundles; collateral. Internalphloem absent. Cortical bundles absent. Medullary bundles present (commonly), orabsent. Secondary thickening anomalous (nearly always), or developing from aconventional cambial ring (rarely?). The anomalous secondary thickening whenpresent (i.e. usually) via concentric cambia (in secondary rings or arcs, theformer giving rise to circles of collateral bundles, the latter resulting intheir being irregularly distributed). Primary medullary rays wide.
The vessels small to medium. The vessel end-walls simple. The vessels withoutvestured pits; without spiral thickening. The axial xylem without fibretracheids; with libriform fibres; without septate fibres. The fibres withoutspiral thickening. The parenchyma paratracheal. ‘Included’ phloempresent (commonly, usually of the concentric type), or absent. The wood storied(Charpenteria,Iresine), or partially storied (?), or not storied(?).
Reproductive type, pollination.Unisexual flowers present, or absent. Plants hermaphrodite (usually),or monoecious, or andromonoecious, or gynomonoecious, or dioecious, orandrodioecious, or polygamomonoecious (rarely).
Inflorescence, floral, fruit and seedmorphology.Flowerssolitary, or aggregated in‘inflorescences’ (usually with conspicuous, persistent bracts andbracteoles); when aggregated, in cymes, or in spikes, or in heads. Theultimate inflorescence units cymose. Inflorescences racemes of cymes; withinvolucral bracts (rarely), or without involucral bracts; pseudanthial, or notpseudanthial.Flowers bracteate; bracteolate; regular; cyclic;tricyclic. Free hypanthium absent (except, dubiously, in somePtilotus species, where the androecial tube is adnate to the calyx).Hypogynous diskabsent.
Perianthsepaline (dry and scarious); 3–5;sepaloid, or petaloid.Calyx 3–5; polysepalous, or gamosepalous(partially); regular; non-fleshy;persistent (dry, stiff and scarious);accrescent (e.g. somePtilotus species), or non-accrescent; imbricate;when K 5, with the median member posterior.
Androecium (1–)2, or 5, or 6–10.Androecial membersfree of the perianth, or adnate (to the perianth or disk);markedly unequal(usually, by contrast with mostChenopodiaceae), or all equal (more orless, e.g. in somePtilotus species);usually basallycoherent (by contrast with mostChenopodiaceae); 1 adelphous(the filaments usually connate for all or part of their length into a membranoustube); 1 whorled.Androeciumexclusively of fertile stamens, orincluding staminodes (commonly, by contrast with mostChenopodiaceae— some androecial members may lack anthers, also there are often‘petaloid enations’ or ‘pseudostaminodial scales’alternating with the true androecial members). Staminodes when present,1–3, or 2, or 3, or 5; in the same series as the fertile stamens; whenpresent, petaloid, or non-petaloid.Stamens(1–)3–5;reduced in number relative to the adjacent perianth, or isomerous with theperianth; oppositisepalous.Anthers dehiscing via longitudinal slits;introrse; unilocular to bilocular; bisporangiate, or tetrasporangiate.Endothecium developing fibrous thickenings, or not developing fibrousthickenings (very rarely). Anther epidermis persistent. Microsporogenesissimultaneous. The initial microspore tetrads tetrahedral, or isobilateral, ordecussate. Anther wall initially with one middle layer; of the‘monocot’ type. Tapetum glandular. Pollen monosiphonous; shed assingle grains. Pollen grains aperturate; 6–20 aperturate; foraminate;spinulose; 3-celled.
Gynoecium 2–3 carpelled.The pistil1 celled.Gynoeciumsyncarpous; synovarious to eu-syncarpous; superior.Ovary1 locular; sessile to stipitate. Gynoecium non-stylate, orstylate. Styles 1–3. Stigmas 1–3; dry type; papillate; Group IItype.Placentationbasal.Ovules in the single cavity 1, or2–5; ascending, or pendulous (but from a basal funicle, subtribeAchyranthinae,Ptilotus etc.); non-arillate;campylotropous;bitegmic; crassinucellate. Outer integument contributing to the micropyle(rarely), or not contributing to the micropyle. Endothelium not differentiated.Polar nuclei fusing prior to fertilization. Antipodal cells formed; initially 3;proliferating (Pupalia), or not proliferating (usually). Synergids hooked(sometimes with filiform apparatus). Endosperm formation nuclear. Embryogenysolanad, or chenopodiad.
Fruit fleshy, or non-fleshy;not an aggregate;dehiscent, or indehiscent; a capsule, or capsular-indehiscent, or a berry, or adrupe, or a nut (often a utricle or nutlet); without fleshy investment externalto the original ovary. Capsules circumscissile (commonly), or splittingirregularly. Seeds non-endospermic (strictly speaking).Perispermpresent (abundant, mealy). Seeds with starch. Embryo well differentiated.Cotyledons 2. Embryo achlorophyllous (1/1); curved. The radicle dorsal. Testasmooth (usually shiny).
Physiology, phytochemistry.C3, or C4, orC3-C4 intermediate. C3 physiology recordeddirectly inAerva,Achyranthes,Alternanthera,Arthraerua,Celosia,Digera,Pupalia. C4physiology recorded directly inAchanthochiton,Aerva,Alternanthera,Amaranthus,Brayulinea,Froelichia,Gomphrena,Gossypianthes,Guillemenia,Lithophila,Tidestromia. C3-C4 intermediacy inAlternantheraficoides andA. tenella.AnatomyC4 type(Acnidia,Achyranthes,Achanthochiton,Aerva,Alternanthera,Amaranthus (see illustration),Brayulinea,Celosia,Froelichia,Gomphrena,Pfaffia,Tidestromia, etc.), or non-C4 type (Achyranthes,Alternanthera,Celosia,Centemopsis,Dasysphaera,Digera,Pupalia,Sericicomopsis etc.).Inulinnot found. Cyanogenic, or not cyanogenic. Alkaloids present, or absent.Iridoids not detected. Betalains present (where sought). Saponins/sapogeninspresent, or absent. Proanthocyanidins absent. Flavonols present, or absent; whenpresent, quercetin. Ellagic acid absent (4 species, 4 genera). Plants oftenaccumulating free oxalates. Sieve-tube plastids P-type; type III (a).
Geography, cytology.Temperate,sub-tropical, and tropical. Widespread.X = 6–13, 17(+).
Taxonomy.Subclass Dicotyledonae;Crassinucelli. Dahlgren’s Superorder Caryophylliflorae; Caryophyllales.Cronquist’s Subclass Caryophyllidae; Caryophyllales. APG III coreangiosperms; core eudicot; Superorder Caryophyllanae. APG IV OrderCaryophyllales.
Species 850. Genera 74;Achyranthes,Achyropsis,Acnida,Aerva,Allmania,Alternanthera,Amaranthus,Arthraerua,Blutaparon,Bosea,Brayulinea,Calicorema,Celosia,Centema,Centemopsis,Centrostachys,Chamissoa,Charpentiera,Chionothrix,Cyathula,Dasysphaera,Dasysphaera,Deeringia,Digera,Eriostylos,Froelichia,Gomphrena,Gossypianthus,Guilleminea,Hebanthe,Hemichroa (~Chenopodiaceae),Henonia,Herbstia,Hermbstaedtia,Indobanalia,Irenella,Iresine,Kyphocarpa,Lagrezia,Leucosphaera,Lithophila,Lopriorea,Marcelliopsis,Mechowia,Nelsia,Neocentema,Nothosaerva,Nototrichium,Nyssanthes,Pandiaka,Pfaffia,Philoxerus,Pleuropetalum,Pleuropterantha,Polyrhabda,Pseudogomphrena,Pseudoplantago,Pseudosericocoma,Psilotrichopsis,Psilotrichum,Ptilotus,Pupalia,Quaternella,Rosifax,Saltia,Sericocoma,Sericocomopsis,Sericorema,Sericostachys,Siamosia,Stilbanthus,Tidestromia,Trichuriella,Volkensinia,Woehleria,Xerosiphon.
Economic uses, etc.A fewcultivated ornamentals, e.g.Amaranthus,Gomphrena,Iresine, and some noxious weeds, notably fromAmaranthus,Iresine,Acnida.
Quotations.
But propt on bedsof amaranth and moly,
How sweet . . . .
To watch the long bright riverdrawing slowly
His waters from the purple hill -
(Tennyson, ‘Songof the Lotos-eaters’)
Illustrations.• Le Maout and Decaisne: Amaranthus, Gomphrena.• Achyranthes angustifolia:Thonner. • Aerva curtisii: Hook.Ic. Pl. 23 (1894). • Amaranthusblitum: Eng. Bot. 177, 1867. • Amaranthus polygonoides: R. Wight,Ic. Pl.Indiae Orientalis 2 (1843). • Amaranthus spinosus: R. Wight,Ic. Pl. IndiaeOrientalis 2 (1843). • Brandesia villosa: Martius, Nova Gen. et Spec. Pl.Brasiliensium 2 (1826). • Celosiacristata var. coccinea: as C. coccinea, Bot. Reg 1834 (1836). • Deeringia amaranthoides (as D. celosioides): Bot.Mag. 54 (1827). • Froelichiafloridana, as Oplotheca: Hook. Ic. Pl. 3 (1840). • Gomphrena desertorum: Martius, Nova Gen. et Spec.Pl. Brasiliensium 2 (1826). • Gomphrena pulchella: Bot. Mag. 70 (1844).• Gomphrena umbellata (as G.pearcei): Hook. Ic. Pl. 11 (1867–71). • Hebanthe spicata: Martius, Nova Gen. et Spec. Pl.Brasiliensium 2 (1826). • Iresineangustifolia, as Rosea elatior: Martius, Nova Gen. et Spec. Pl. Brasiliensium 2(1826). • Iresine herbstii: Bot.Mag. 91 (1865). • Microgynoeciumtibeticum: Hook. Ic. Pl. 24 (1895). • Pleuropetalum sprucei (as P. costaricense): Bot.Mag. 109 (1883). • Pfaffiaglabrata: Martius, Nova Gen. et Spec. Pl. Brasiliensium 2 (1826).• Ptilotus crosslandii (asDipteranthemum): Hook. Ic. Pl. 16 (1886). • Ptilotus polystachyus: Bot. Reg. 1839, 28.• Ptilotus spathulatus (asTrichinium): Hooker, Fl. Tasmaniae (1860). • Stilbanthus scandens: Hook. Ic. Pl. 13(1877–79). • Leaf anatomy(Solereder, 1908). • Aerva andBosea: anomalous stem anatomy (Solereder, 1908).
We advise against extracting comparative informationfrom the descriptions. This is much more easily achieved using theDELTA data files or theinteractive key, which allows access to the characterlist, illustrations, full and partial descriptions, diagnostic descriptions,differences and similarities between taxa, lists of taxa exhibiting or lackingspecified 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 alsoGuidelines for using data taken from Web publications.
Cite this publication as: ‘Watson, L., andDallwitz, M.J. 1992 onwards. The families of flowering plants: descriptions,illustrations, identification, and information retrieval. Version: 25th March2025.delta-intkey.com’.
