The World Flora Online

Herbs, shrubs, or small trees, sometimes monoecious or dioecious. Stems erect, prostrate, twining, or scandent, often with swollen nodes, striate, grooved, or prickly. Leaves simple, alternate, rarely opposite or whorled, petiolate or subsessile; stipules often united to a sheath (ocrea). Inflorescence terminal or axillary, spicate, racemose, paniculate, or capitate. Pedicel occasionally articulate. Flowers small, actinomorphic, bisexual, rarely unisexual. Perianth 3-6-merous, in 1 or 2 series, herbaceous, often enlarged in fruit or inner tepals enlarged, with wings, tubercles, or spines. Stamens usually (3-)6-9, rarely more; filaments free or united at base; anthers 2-loculed, opening lengthwise; disk annular (often lobed). Ovary superior, 1-loculed; styles 2 or 3, rarely 4, free or connate at lower part. Fruit a trigonous, biconvex, or biconcave achene; seed with straight or curved embryo and copious endosperm.

Seeds with abundant mealy endosperm and often excentric embryo Ovary superior, sessile, 1-celled; styles 2–4, usually free; ovule solitary, basal, sessile or stalked Fruit an indehiscent trigonous or 2-sided nut Flowers hermaphrodite, polygamous or dioecious, actinomorphic, small and inconspicuous Stamens usually 6–9, rarely more; filaments free or united at the base; anthers 2-celled, opening lengthwise Disk annular or central Sepals 3–6, imbricate, often enlarged and becoming membranous in fruit Petals absent Herbs, shrubs or climbers, rarely trees: leaves alternate, with the base of the petiole often dilated into a membranous sheath (ochrea) Ovary superior, sessile, 1-celled; styles 2–4, usually free; ovule solitary, basal, sessile or stalked Fruit an indehiscent trigonous or 2-sided nut Flowers hermaphrodite, polygamous or dioecious, actinomorphic, small and inconspicuous Stamens usually 6–9, rarely more; filaments free or united at the base; anthers 2-celled, opening lengthwise Disk annular or central Sepals 3–6, imbricate, often enlarged and becoming membranous in fruit Petals absent Herbs, shrubs or climbers, rarely trees: leaves alternate, with the base of the petiole often dilated into a membranous sheath (ochrea)

Besides the above indigenous genera, Antigonon leptopus Hook. & Arn., a native of Mexico, is often met with; it is widely cultivated as an ornamental and is known as "Corallita."

Fls relatively small, perfect or unisexual; tep 2–6, basally connate into a minute or evident floral tube, green and herbaceous to often colored and ± petaloid, most often in 2 similar or slightly dissimilar cycles of 3, but not clearly differentiated into sep and pet, sometimes 5 and spirally uniseriate; stamens 2–9, rarely more, most commonly 3 + 3, but not infrequently 8 (notably in spp. of Polygonum); filaments distinct or basally connate; ovary superior, unilocular, (2)3(4)-carpellate, with distinct or basally united styles; ovule solitary on a basal placenta; fr an achene or small nut, lenticular or often trigonous, sometimes closely subtended by the persistent, sometimes accrescent tepals, or enclosed in a fleshy hypanthium; seeds with copious endosperm; embryo straight or curved; commonly excentric or peripheral (seldom centric), with 2 cotyledons; herbs (almost all ours) or less often woody plants, sometimes climbing or twining, producing anthocyanins but not betalains; lvs mostly alternate, seldom opposite or whorled, simple and usually entire, seldom cleft, sometimes articulate at base; stipules commonly well developed and connate into a usually scarious or hyaline (often bilobed or fringed) sheath (ocrea) around the stem, or (notably in Eriogonum) sometimes much reduced or wanting; fls borne in various sorts of infls, often in small, involucrate fascicles, often individually subtended by a persistent ocreola, evidently articulate to the pedicel, and often with a distinctly stipitate base above the articulation. 30/1000.

Plantes'herbacées ou ligneuses, parfois monoïques ou dioïques.'Feuilles'généralement alternes, à pétiole muni d'une ochréa bien développée à bords ciliés ou non mais parfois réduite à une crête annulaire.'Fleurs'solitaires ou en fascicules cymeux à l'aisselle de bractées souvent ochréiformes et groupés en inflorescences variées, à bractéoles nulles, 1 ou 2 et alors soudées en gaine, petites, ☿ ou ♂ ♀, 3-mères ou pseudo-5-4-mères; périgone homochlamydé, ± gamophylle en tube à la base ou à tépales libres, verdâtre ou coloré, persistant et souvent accrescent; androcée variable par suite de dédoublements et d'avortements, à 5-9 étamines toutes fertiles ou certaines staminodiales, à filets insérés sur le réceptacle, parfois ± monadelphes à la base, à anthères basi- ou dorsifixes, à 2 thèques déhiscentes longitudinalement; gynécée à 2-3 carpelles; ovaire comprimé ou trigone, 1-loculaire et à 1 ovule basilaire dressé; styles 2-3, libres ou unis à la base, à stigmates capites, lobés ou pénicillés.'Akènes'souvent accompagnés du périgone persistant et généralement membraneux, lenticulaires, trigones ou ovoïdes.'Graines à albumen abondant, uni ou ruminé et à embryon courbe ou droit, à cotylédons variables.\n\t\t\tFamille cosmopolite, renfermant environ 36 genres groupant 800 espèces répandues principalement dans les régions boréales, beaucoup plus rares sous les tropiques où elles se rencontrent surtout dans les régions d'altitude.

Herbs, climbers, shrubs, or trees (not in tropical East Africa) Stamens 5–9 inE. African spp., usually all fertile, inserted in 1 or 2 series at or near the base of the perianth; filaments filiform throughout or basally dilated, free or conjoined at the base; anthers 2–celled, longitudinally dehiscent Perianth inferior, calyciform with 3–6 free, sometimes petaloid lobes (tepals) arranged in 1 or 2 series, often accrescent and then sometimes armed with spines, prickles or teeth Petals 0 Inflorescence capitate, racemose, or ± umbellate, often branched and paniculate Flowers actinomorphic; hermaphrodite, polygamous, dioecious, or monoecious; borne in many- or few-flowered fascicles, pedicellate, subtended or not by ocreiform bracts with or without bracteoles Leaves usually alternate, often lush, sessile or stalked, usually dilated into an amplexicaul cup (ocrea) at the junction with the stem Branches sometimes tendrilous Styles 2–3, free or connate below, the flowers sometimes heterostylous; stigmas capitate, dilated, fimbriate or penicillate Seed with abundant endosperm Ovule solitary, basal, sessile or stalked Mature fruit nut-like, fusiform, lenticular, or acutely or obscurely trigonous, unarmed or armed with prickles or (Harpagocarpus) barbed setae Ovary 1–locular, superior, sessile Stamens 5–9 inE. African spp., usually all fertile, inserted in 1 or 2 series at or near the base of the perianth; filaments filiform throughout or basally dilated, free or conjoined at the base; anthers 2–celled, longitudinally dehiscent Perianth inferior, calyciform with 3–6 free, sometimes petaloid lobes (tepals) arranged in 1 or 2 series, often accrescent and then sometimes armed with spines, prickles or teeth Petals 0 Inflorescence capitate, racemose, or ± umbellate, often branched and paniculate Flowers actinomorphic; hermaphrodite, polygamous, dioecious, or monoecious; borne in many- or few-flowered fascicles, pedicellate, subtended or not by ocreiform bracts with or without bracteoles Leaves usually alternate, often lush, sessile or stalked, usually dilated into an amplexicaul cup (ocrea) at the junction with the stem Branches sometimes tendrilous Styles 2–3, free or connate below, the flowers sometimes heterostylous; stigmas capitate, dilated, fimbriate or penicillate Seed with abundant endosperm Ovule solitary, basal, sessile or stalked Mature fruit nut-like, fusiform, lenticular, or acutely or obscurely trigonous, unarmed or armed with prickles or (Harpagocarpus) barbed setae Ovary 1–locular, superior, sessile

Certain species have value as crops, as vegetables, or as medicines

Two genera are confined to Africa and Madagascar A world-wide family, most abundant in temperate regions A world-wide family, most abundant in temperate regions

SELECTED REFERENCES

Brandbyge, J. 1993. Polygonaceae. In: K. Kubitzki et al., eds. 1990+. The Families and Genera of Vascular Plants. 4+ vols. Berlin etc. Vol. 2, pp. 531-544. Carlquist, S. 2003. Wood anatomy of Polygonaceae: Analysis of a family with exceptional wood diversity. Bot. J. Linn. Soc. 141: 25-51. Graham, S. A. and C. E. Wood Jr. 1965. The genera of Polygonaceae in the southeastern United States. J. Arnold Arbor. 46: 91-113. Jaretzky, R. 1928. Histologische und karyologische Studien an Polygonaceen. Jahrb. Wiss. Bot. 69: 357-490. Lamb Frye, A. S. and K. A. Kron. 2003. rbcL phylogeny and character evolution in Polygonaceae. Syst. Bot. 28: 326-332. Laubengayer, R. A. 1937. Studies in the anatomy and morphology of the polygonaceous flower. Amer. J. Bot. 24: 329-343. Roberty, G. E. and S. Vautier. 1964. Les genres de Polygonacées. Boissiera 10: 7-128.

Trees, shrubs, vines, or herbs, perennial, biennial, or annual, homophyllous (heterophyllous in some species of Polygonum), polycarpic (rarely monocarpic in Eriogonum); roots fibrous or a solid or, rarely, chambered taproot, rarely tuberous. Stems prostrate to erect, sometimes scandent or scapose, solid or hollow, rarely with recurved spines (some species of Persicaria), glabrous or pubescent, sometimes glandular; nodes swollen or not; tendrils absent (except in Antigonon and Brunnichia); branches free (adnate to stems distal to nodes and appearing to arise internodally in Polygonella); caudex stems (subfam. Eriogonoideae) tightly compact to spreading and at or just below the soil surface or spreading to erect and above the soil surface, woody; aerial flowering stems prostrate or decumbent to erect, arising at nodes of caudex branches, at distal nodes of aerial branches, or directly from the root, slender to stout and solid or slightly to distinctly fistulose, rarely disarticulating in ringlike segments (Eriogonum). Leaves deciduous (persistent in Coccoloba and sometimes more than 1 year in Antigonon, Eriogonum, Chorizanthe, and Polygonella), basal or basal and cauline, rosulate, mostly alternate, infrequently opposite or whorled; stipule (ocrea) absent (subfam. Eriogonoideae, possibly vestigial in some perennial species of Chorizanthe) or present (subfam. Polygonoideae), persistent or deciduous, cylindric to funnelform, sometimes 2-lobed (Polygonum), chartaceous, membranous, coriaceous or partially to entirely foliaceous; petiole present or absent, rarely articulate basally (Fagopyrum, Polygonella, Polygonum), rarely with extrafloral nectaries (Fallopia, Muehlenbeckia); blade simple, margins entire, occasionally crenulate, crisped, undulate, or lobed, rarely awn-tipped (Goodmania). Inflorescences terminal or terminal and axillary, cymose and dichotomously or trichotomously branched, or racemose, umbellate, or capitate (subfam. Eriogonoideae; or spikelike, racemelike, paniclelike, cymelike, or, rarely, capitate (subfam. Polygonoideae), comprising simple or branched clusters of compound inflorescences; bracts absent (subfam. Polygonoideae), or 2-10+, usually connate proximally or to 1/ 2 their length, rarely perfoliate, foliaceous or scalelike, margins entire, sometimes awn-tipped (subfam. Eriogonoideae, rarely absent in Eriogonum), glabrous or pubescent; peduncle present or absent; clusters of flowers subtended by involucral bracts or enclosed in typically nonmembranous tubular involucres (subfam. Eriogonoideae) or subtended by connate bracteoles forming a persistent membranous tube (ocreola) (subfam. Polygonoideae). Pedicels present or absent, rarely accrescent (Brunnichia), articulate to flowers. Flowers usually bisexual, sometimes bisexual and unisexual on same or different plants, rarely unisexual only, 1-many, often with stipelike base distal to articulation; perianth persistent, often accrescent in fruit, often greenish, white, pink, yellow, red, or purple, rarely winged or keeled (Fallopia and some species of Polygonum), campanulate to urceolate, sometimes membranous, indurate (Brunnichia and Emex), or fleshy (Coccoloba, Muehlenbeckia, and some species of Persicaria) in fruit, rarely developing raised tubercles proximally (Rumex), glabrous or pubescent, sometimes glandular or glandular-punctate; tepals 2-6, distinct or connate proximally and forming tube, usually in 2 whorls, petaloid or sepaloid, dimorphic or monomorphic, rarely coriaceous (Lastarriaea), entire, emarginate, or lobed to laciniate apically, rarely awn-tipped (Lastarriaea); nectary a disk at base of ovary or glands associated with bases of filaments; stamens (1-)6-9,

Annual or perennial herbs, shrubs or climbers (more rarely trees), glabrous or hairy Perianth sepaloid or petaloid of 3–6 free or connate segments (tepals), in 1 or 2 series, imbricate in bud, membranous, sometimes accrescent, sometimes armed with spines, prickles or teeth Stamens (4)6–9, usually inserted at or near the base of the perianth segments; filaments filiform or dilated at the base, free or basally united; anthers dorsifixed, 2-thecous, opening lengthwise Inflorescences capitate, racemose or ± umbellate, sometimes branched and paniculate, the flowers usually fascicled and subtended by bracts as well as the ocrea, with or without bracteoles Flowers hermaphrodite, polygamous or unisexual, sometimes heterostylous, actinomorphic, pedicellate; pedicels usually articulated Branches sometimes with tendrils Leaves usually alternate and usually with sheathing stipules (ocreae) Seed similar in shape to the nut, with abundant endosperm; testa membranous, smooth or not Fruit a nut, indehiscent, hard, trigonous or lenticular, usually enclosed in the ± persistent perianth Ovary superior, syncarpous, unilocular, sometimes falsely 3-locular, with a solitary basal orthotropous ovule; styles 2–3, free, or connate at the base; stigmas capitate, peltate or penicillate Disk annular or composed of glands Perianth sepaloid or petaloid of 3–6 free or connate segments (tepals), in 1 or 2 series, imbricate in bud, membranous, sometimes accrescent, sometimes armed with spines, prickles or teeth Stamens (4)6–9, usually inserted at or near the base of the perianth segments; filaments filiform or dilated at the base, free or basally united; anthers dorsifixed, 2-thecous, opening lengthwise Inflorescences capitate, racemose or ± umbellate, sometimes branched and paniculate, the flowers usually fascicled and subtended by bracts as well as the ocrea, with or without bracteoles Flowers hermaphrodite, polygamous or unisexual, sometimes heterostylous, actinomorphic, pedicellate; pedicels usually articulated Branches sometimes with tendrils Leaves usually alternate and usually with sheathing stipules (ocreae) Seed similar in shape to the nut, with abundant endosperm; testa membranous, smooth or not Fruit a nut, indehiscent, hard, trigonous or lenticular, usually enclosed in the ± persistent perianth Ovary superior, syncarpous, unilocular, sometimes falsely 3-locular, with a solitary basal orthotropous ovule; styles 2–3, free, or connate at the base; stigmas capitate, peltate or penicillate Disk annular or composed of glands