Potentilla sect. Pentaphylloides |
Rosaceae subfam. rosoideae |
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Habit | Perennials, openly matted, stoloniferous [to ± tufted, not stoloniferous]; taproots not fleshy-thickened, often absent and replaced by ± thickened lateral roots; vestiture primarily of long and crisped-cottony hairs, glands absent or sparse, not red. | Herbs, shrubs, or subshrubs. |
Stems | prostrate [to erect], flagelliform [or not], rooting at nodes [or not], lateral to ± persistent basal rosettes, 1–10+ dm, lengths (0.5–)1–5+ times basal leaves. |
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Leaves | basal not or ± 2-ranked; cauline (between flowering and/or rosette-forming nodes) 0–1; primary leaves pinnate (distal leaflets sometimes confluent), (1–)3–50(–75) cm; petiole: long hairs absent or ascending to weakly appressed, sometimes spreading, soft to weak, glands absent or very sparse; primary leaflets (5–)7–21(–31[–51]) plus additional small leaflets interspersed, on distal (1/2–)2/3–4/5+ of leaf axis, overlapping or not, elliptic to obovate, margins revolute or nearly flat, distal (1/2–)2/3–3/4+ evenly incised 1/4–1/2 to midvein, teeth (2–)5–12(–16) per side, surfaces similar to strongly dissimilar, abaxial usually white, sometimes green, cottony(/crisped) hairs usually dense, sometimes sparse or absent, adaxial green to white, not glaucous, long hairs absent or weak to soft. |
alternate, rarely opposite, pinnately compound, sometimes simple or palmately compound; stipules present, rarely absent. |
Inflorescences | solitary flowers at stolon nodes [± cymose]. |
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Pedicels | straight in fruit, (1–)2–45(–55) cm. |
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Flowers | 5(–7)-merous; hypanthium 3–7 mm diam.; petals bright yellow, elliptic to broadly elliptic, (4–)5–15(–20) mm, longer than sepals, apex rounded or slightly retuse; stamens [5–]20(–30); styles ± lateral [subapical or sub-basal], narrowly columnar-filiform, not papillate-swollen proximally, 1.5–2.5 mm. |
torus usually enlarged, sometimes small or absent; carpels 1–260(–450), distinct, free, styles distinct, rarely connate (Roseae); ovules 1(or 2), collateral (Rubeae) or superposed (Fallugia, Filipendula). |
Fruits | achenes or aggregated achenes sometimes with fleshy, urn-shaped hypanthium or enlarged torus, sometimes aggregated drupelets; styles persistent or deciduous, not elongate (elongate but not plumose in Geum). |
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Achenes | slightly rugose and papillate. |
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x | = 7(8). |
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Potentilla sect. Pentaphylloides |
Rosaceae subfam. rosoideae |
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Distribution | North America; Mexico; South America (Argentina, Chile); Eurasia; Pacific Islands (New Guinea, New Zealand); s Australia |
North America; Mexico; Central America; South America; West Indies; Bermuda; Eurasia; Africa; Atlantic Islands; Indian Ocean Islands; Pacific Islands; Australia |
Discussion | Species ca. 50 (1 in the flora). The use here of sect. Pentaphylloides is contrary to the argument by J. Soják (2007) that the use of Pentaphylloides Tournefort by G. R. Boehmer (in C. G. Ludwig 1760) qualified as an unranked infrageneric taxon, making sect. Pentaphylloides Tausch a later homonym. In that Boehmer was citing synonyms, not infrataxa, sect. Pentaphylloides Tausch is the correct name for this section. The names sect. Chenopotentilla Focke and sect. Leptostylae (Th. Wolf) Guşuleac are superfluous and illegitimate. Potentilla anserina is the atypical and only representative in North America of a primarily southeastern Asian section. Although provisionally retained within Potentilla, the morphological distinctiveness of the section has led to the recognition of Argentina as a segregate genus (for example, P. A. Rydberg 1908d; Á Löve and D. Löve 1975b; B. C. Johnston 1985; J. Soják 2010). Molecular analyses (C. Dobeš and J. Paule 2010; M. H. Töpel et al. 2011) have confirmed the section is a strongly supported monophyletic clade, albeit including some other Asian species treated by J. Soják (1994) as the segregate genera Piletophyllum (Soják) Soják and Tylosperma Botschantzev. Chloroplast markers (Dobeš and Paule; Töpel et al.) place this clade sister to all other Potentilleae; nuclear markers (Töpel et al.) indicate instead a sister relation to Fragariinae. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Variation in the number of genera in subfam. Rosoideae is due to differences in generic delimitation between D. Potter et al. (2007) and the authors of some Potentilleae genera. Cyanogenic glycosides and sorbitol are absent in the subfamily. Tribes 6, genera 28–35, species ca. 1600 (6 tribes, 26 genera, 302 species, including 1 hybrid, in the flora) (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 9, p. 126. | FNA vol. 9, p. 23. |
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Synonyms | section Argentina, P. section Anserina, P. ser., P. subg. Argentina | |
Name authority | Tausch: Hort. Canal., sub P. ornithopoda. 1823 | Arnott: Botany, 107. (1832) |
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