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4. Potentilla L., Sp. Pl. 495. 1753. Gen. Pl. ed. 5. 219. 1754, Lehm., Monogr. Potent. 1820, Revis. Potent. 1856, Hook. f., Fl. Brit. Ind. 2:345. 1878, Juz. in Kom. Fl. USSR 10: 78. 1941, Ball et al. in Tutin et al. Fl. Europ. 2: 36. 1968, Schiman-Czeika in Rech. f., Fl. Iran. 66: 78. 1969, Pesmen in P. H. Davis, Fl. Turk. 4: 41. 1972, Grierson & D. G. Long, Fl. Bhut. 1 (3): 562 1987, Dikshit & Panigrahi, Rosaceae Ind. 4: 40-247. 1998.
Muqarrab Shah
Department of Microbiology, Hazara University, Mansehra, Pakistan
Perennials, rarely annual herbs or shrubs. Rootstock profusely divided to undivided, covered with remains of dead stipules. Stem generally herbaceous, rarely woody or semi-woody, erect, ascending or prostrate, rarely stoloniferous, pilose to tomentose. Leaves 3-5 to many foliolate, digitate or pinnate, mostly forming rosettes at the base, rarely without rosettes. Basal stipules entire, auriculate, upper stipules green and leafy, entire or divided. Leaflets entire to dentate to segmentate, pilose or tomentose, rarely subglabrous. Inflorescence solitary, or 2-flowered to many flowered (usually in terminal cymes). Flowers generally 5-merous and bisexual, rarely unisexual, with rudimentary stamens or carpels. Calyx of 10 sepals in two rows, outer generally oblong-obtuse, inner ovate-actue. Petals generally yellow, rarely white or red, obovate or obcordate, apices rounded or emarginate. Stamens generally 20, mono- or dithecous, attached near the base of the carpophore. Carpels numerous, styles generally subterminal, rarely sub-basal or lateral, generally clavate, coniform or filiform, rarely fusiform and rod-shaped. Achenetum borne generally on flat receptacle, rarely on globose receptacle falling off individually, generally glabrous, rarely with short or long hairs, surface smooth or ridged.
The genus Potentilla has about 500 species, distributed mostly in the northern hemisphere. In Pakistan it is represented by about 52 species and some hybrids. The taxonomy of some of the species is complicated by the presence of a range of intermediates resulting from frequent hybridization, pseudogamy and apomixis.
Key to the subgenera
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1 |
Anthers monothecous. |
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(2) |
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Anthers dithecous. |
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(5) |
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2 (1) |
Petioles and petiolules articulated at the base, auricles of stipules partly fused. |
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4 Potentilla Subgenus Dasiphora |
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Petioles and petiolules not articulated at the base, auricles of stipules free. |
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(3) |
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3 (2) |
Leaves ternate |
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4 Potentilla Subgenus Sibbaldiopsis |
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Leaves pinnate |
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(4) |
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4 (3) |
Flowering stem herbaceous, leaflets not farinose beneath, styles fusiform, short. |
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4 Potentilla Subgenus Schistophyllidium |
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Flowering stem lignescent, leaflets farinose beneath, styles filiform, very long. |
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4 Potentilla Subgenus Lasiocarpa |
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5 (1) |
Styles lateral. |
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(6) |
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Styles subterminal. |
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(7) |
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6 (5) |
Woody subshrubs, carpels hairy, styles very long |
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4 Potentilla Subgenus Trichothalamus |
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Herbaceous, carpels glabrous, styles shorter. |
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4 Potentilla Subgenus Chenopotentilla |
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7 (5) |
Receptacle long-villose, carpels generally hairy. |
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4 Potentilla Subgenus Fragariastrum |
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Receptacle shortly hairy, carpels glabrous. |
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4 Potentilla Subgenus Potentilla |
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List of lower taxa
Related Links (opens in a new window) |
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