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13. Rumex Linnaeus, Sp. Pl. 333. 1753; Gen. Pl. ed. 5: 156. 1754; Boiss., Fl. Or. 4: 1003. 1879; Hook.f., Fl. Brit. Ind. 5: 58. 1886; Rech.f. in Feddes Rep. 31: 225-283. 1933; in Candollea 12: 9-132. 1949; in Tutin et al., Fl. Europ. 1: 82. 1964; Fl. Iran. 56: 2. 1968; Losinsk. in Kom., Fl. URSS 5: 444. 1936; Cullen in P.H.Davis, Fl. Turk. 2: 281. 1966; Grierson & D.G.Long, Fl. Bhutan 1: 173. 1983; Munshi & Javeid, Syst. Stud. Polygon. Kashm. Himal. 86. 1986; Boulos, Fl. Egypt 1: 30. 1999; Chaudhary, Fl. Kingd. Saudi Arab. 1: 308. 1999.
Herbs, rarely shrubs usually with long, stout roots, sometimes rhizomatous. Leaves alternate, basal and cauline; ochreae tubular. membranous, often entire. Flowers hermaphrodite or unisexual, arranged in whorls forming simple or branched inflorescences, anemophilous. Perianth-segments in two whorls of 3, the outer remaining small and thin, the inner becoming enlarged and often hardened in fruit. Valves (fruiting inner perianth segments) sometimes developing marginal teeth or dorsal tubercles as they mature. Stamens in two whorls of 3; anthers basifixed. Fruit a trigonous nut.
A genus of more than 200 species, distributed in temperate regions especially in the Northern areas of both parts of the world; represented in Pakistan by 15 species and 2 hybrids.
The range of variability of several species as well as their distributional areas are still incompletely known. Hybrids between many species of Subgenus Rumex (species nrs. 4-15) occur frequently.
In nature hybrids of Rumex may be recognized by their appearance. The primary panicles sheds most of the sterile flowers but the plants continue to grow and tend to form secondary flowering panicles. Thus the hybrids are often taller than the parents and assume an untidy habit. Additionally most hybrids fail to set fruit because the flowers dry and fall off before full development of the valves (i.e. the three inner perianth segments) occurs. The few valves which do reach full size exhibit the characters of the parents in various ways. Often these hybrid nuts, even if reaching full size, are not viable and can be compressed between the fingers.
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1 |
Leaves hastate or sagittate. Flowers dioecious or polygamous. |
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(2) |
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Leaves never hastate or sagittate. Flowers normally androgynous. |
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(4) |
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2 (1) |
Annual. Valves very large, up to 20 mm in diam. Flowers and fruits normally in twins on a common pedicel. |
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3 R. vesicarius |
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Perennial or suffrutescent. Valves much smaller. Flower and fruits not as above. |
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(3) |
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3 (2) |
Suffrutescent, richly branching. |
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1 R. hastatus |
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Plants perennial, herbaceous, with leafy branched stem. |
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2 R. acetosa |
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4 (1) |
Valves grainless. |
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(5) |
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Valves all or at least the anterior with a grain. |
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(7) |
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5 (4) |
Lower leaves small, lanceolate. Panicle narrow, with few single simple short branches. |
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4 R. angulatus |
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Lower leaves large oblong-ovate, with cordate base. Panicle very large, lower branches fasciculate and richly branching. |
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(6) |
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6 (5) |
Pedicels 15-20 mm long, articulate near the base. Valves nearly entire, the anterior with a minute elongate grain. |
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6 R. arcuatoramosus |
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Pedicels 25-35 mm long, articulate at half of their length. Valves nearly entire without grain, with middle nerve slightly increassate towards the base. |
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5 R. paulsenianus |
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7 (4) |
Valves entire. |
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(8) |
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Valves not entire. |
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(12) |
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8 (7) |
Valves very small, 2.5-3.5 mm long. |
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(9) |
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Valves larger. |
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(10) |
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9 (8) |
Panicle narrow, dense, branches few, erect. Whorls distant, without subtending leaves. Valves rotundate-cordate; grains much smaller than the valves. |
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10 R. crispellus |
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Panicle broad, open, branches many, broadly arcuate-divaricate. Whorls remote, nearly all subtended by a leaf. Valves lingulate, each with a prominent grain covering most of the valve surface. |
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11 R. conglomeratus |
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10 (8) |
Stem usually 1-2 m high. Basal leaves oblong-ovate, with cordate base. Panicle very large, lower branches fasciculate and repeatedly branching. Fruiting pedicels of varying length, partly 2-3.5 times as long as the valve. |
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7 R. thjanschanicus |
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Stem lower. Basal leaves lanceolate or oblong-lanceolate with cuneate or truncate base. Panicle narrower. Fruiting pedicels shorter. |
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(11) |
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11 (10) |
Basal leaves oblong, up to 3 times longer than broad. |
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8 R. patientia |
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Basal leaves lanceolate, more than 3 times as long as broad. |
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9 R. crispus |
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12 (7) |
Annual. Stem branching from near the base or unbranched. Leaves small. |
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14 R. dentatus |
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Perennial. Stem paniculate above the middle. |
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(13) |
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13 (12) |
Teeth of valves hooked at the apex. |
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13 R. nepalensis |
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Teeth of valves not hooked. |
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(14) |
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14 (13) |
Pedicels up to twice as long as the valve. Valves cordate with acute tip with 4-9 unequal teeth near the base. |
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12 R. chalepensis |
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Pedicels about as long as the valve. Valves broadly cordate-scutiform with broadly attenuate apex, irregularly incise-denticulate towards the base. |
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15 R. punjabensis |
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List of lower taxa
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