Including Subscariosaceae Dulac
Habit and leaf form. Shrubs (usually), or herbs. With neither basal nor terminal aggregations of leaves. Self supporting, or climbing (occasionally). Leaves alternate, or opposite; sheathing, or non-sheathing; simple. Lamina entire; pinnately veined. Leaves exstipulate. Lamina margins entire. Domatia commonly recorded.
General anatomy. Plants commonly with `crystal sand'.
Leaf anatomy. Abaxial epidermis not papillose.
Adaxial hypodermis absent. Main veins embedded. Minor leaf veins without phloem transfer cells (Amaranthus, Celosia).
Stem anatomy. Cork cambium present; initially superficial. Nodes unilacunar. Primary vascular tissue centrifugal. Cortical bundles absent. Medullary bundles present (commonly), or absent. Internal phloem absent. Secondary thickening developing from a conventional cambial ring, or anomalous; when anomalous, via concentric cambia. `Included' phloem present, or absent. Xylem with libriform fibres; with vessels. Vessel end-walls simple. Primary medullary rays wide. Wood storied (Charpenteria, Iresine), or partially storied (?), or not storied (?); parenchyma paratracheal. Sieve-tube plastids P-type; type III (a).
Reproductive type, pollination. Hermaphrodite (usually), or monoecious, or andromonoecious, or gynomonoecious, or dioecious, or androdioecious, or polygamomonoecious (rarely).
Inflorescence, floral, fruit and seed morphology. Flowers solitary, or aggregated in `inflorescences' (usually with conspicuous, persistent bracts and bracteoles); in cymes. The terminal inflorescence unit when flowers aggregated, cymose. Inflorescences racemes of cymes; pseudanthial, or not pseudanthial. Flowers bracteate; bracteolate; regular; cyclic; tetracyclic. Free hypanthium absent. Hypogynous disk absent.
Perianth sepaline (dry and membranous); 3-5. Calyx 3-5; polysepalous, or gamosepalous (partially); regular; when K 5, with the odd member posterior.
Androecium (1-)2, or 5, or 6-10. Androecial members free of the perianth, or adnate (to the perianth or disk); markedly unequal; usually coherent; 1 - adelphous (the filaments usually connate for all or part of their length into a membranous tube); 1 - whorled. Androecium exclusively of fertile stamens, or including staminodes (in that `petaloid enations' sometimes alternate with the anthers). Staminodes when present, 2, or 3, or 5; when present, petaloid. Stamens (1-)3-5; oppositisepalous. Anthers dehiscing via longitudinal slits; introrse; unilocular to bilocular; bisporangiate, or tetrasporangiate. Endothecium developing fibrous thickenings, or not developing fibrous thickenings (very rarely). Anther epidermis persistent. Microsporogenesis simultaneous. The initial microspore tetrads tetrahedral, or isobilateral, or decussate. Anther wall initially with one middle layer; of the `monocot' type. Tapetum glandular. Pollen monosiphonous; shed as single grains. Pollen grains aperturate; 6-20 - aperturate; foraminate; 3-celled.
Gynoecium 2-3; syncarpous; synovarious to synstylovarious; superior. Ovary 1 locular. Styles 1-3. Stigmas 1-3; dry type; papillate; Group II type. Placentation basal. Ovules in the single cavity 1, or 2-5; ascending; 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. Embryogeny solanad, or chenopodiad.
Fruit fleshy, or non-fleshy; dehiscent, or indehiscent; a capsule, or capsular-indehiscent, or a berry, or a drupe, or a nut (often a utricle or nutlet). Capsules circumscissile. Seeds non-endospermic (strictly speaking). Perisperm present (abundant, mealy). Seeds with starch. Embryo well differentiated. Cotyledons 2. Embryo achlorophyllous (1/1); curved. Testa smooth (usually shiny).
Physiology, biochemistry. Cyanogenic, or not cyanogenic. Alkaloids present, or absent. Iridoids absent. Proanthocyanidins absent. Flavonols present, or absent; when present, quercetin. Ellagic acid absent (4 species, 4 genera). Betalains present. Saponins/sapogenins present, or absent. Plants often accumulating free oxalates. C3 and C4, or C3-C4 intermediate. C3 recorded in Aerva, Achyranthes, Alternanthera, Arthraerua, Celosia, Digera, Pupalia. C4 recorded in Achanthochiton, Aerva, Alternanthera, Amaranthus, Brayulinea, Froelichia, Gomphrena, Gossypianthes, Guillemenia, Lithophila, Tidestromia. C3-C4 intermediacy in Alternanthera ficoides and A. tenella. Anatomy C4 type (Acnidia, Achyranthes, Achanthochiton, Aerva, Alternanthera, Amaranthus, Brayulinea, Celosia, Froelichia, Gomphrena, Pfaffia, Tidestromi, etc.), or non-C4 type (Achyranthes, Alternanthera, Celosia, Centemopsis, Dasysphaera, Digera, Pupalia, Sericicomopsis etc.).
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. Takhtajan's Subclass Caryophyllidae; Caryophyllanae; Caryophyllales. Species 850. Genera 74; Achyranthes, Achyropsis, 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, 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 few cultivated ornamentals, e.g. Amaranthus, Gomphrena, Iresine, and some noxious weeds, notably from Amaranthus, Iresine, Acnida.
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