Salsola kali |
Salsola |
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common saltwort, prickly Russian thistle, Russian thistle, saltwort, tumbleweed |
Russian-thistle, salsovie, saltwort, soude, tumbleweed |
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Habit | Herbs, 5–50 cm, papillose to hispid or, occasionally, glabrous. | Herbs, annual, or subshrubs [shrubs and small trees], glabrous, or ± pubescent or hispid. | ||||||||||||||||||||||||||||
Stems | erect to ascending, branched from base; branches arcuate or, occasionally, almost prostrate. |
erect, ascending, or prostrate, branched (rarely simple), not jointed, not armed, not fleshy. |
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Leaves | alternate; blade linear, mostly 1–2 mm wide in herbarium specimens, fleshy, usually not swollen at base, apex ± acuminate into rather firm, 1–1.5(–2.2) mm spine. |
mostly alternate (rarely opposite, especially proximal ones), sessile; blade lanceolate, linear, or filiform to subulate, semiterete, margins entire basally, apex obtuse, soft and subspinescent or narrowed to spine or soft bristle. |
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Inflorescences | interrupted at maturity, usually 1-flower per axil of bract; bracts alternate, not imbricate at maturity, reflexed, not distinctly swollen at base, apex narrowing into subulate spine. |
spicate, flowers solitary in axils of bracts or reduced distal leaves (rarely 2–3-flowered with lateral flowers poorly developed); bracts ovate-lanceolate, spine-tipped. |
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Flowers | bracteoles free or becoming connate and adnate to perianth base; perianth segments with comparatively narrow wing or in lower flowers occasionally wingless (in S. kali subsp. pontica sometimes prominently winged), with weak or firm, acute apex, glabrous; fruiting perianth 4–6(–8) mm diam. 2n = 36. |
bisexual, with 2 bracteoles; perianth segments persistent, 5, covering utricle at maturity, often developing transverse, dorsal, membranous or ± coriaceous wing (sometimes only 2–3 segments winged, sometimes wingless or nearly so); stamens 5; styles and stigmas 2 (or 3). |
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Fruits | utricles, covered by perianth segments at maturity; pericarp adherent. |
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Seeds | usually horizontal, orbicular; seed coat black or brown; perisperm absent. |
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x | = 9. |
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Salsola kali |
Salsola |
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Distribution |
AL; CA; CT; DC; DE; FL; GA; LA; MA; MD; ME; MS; NC; NH; NJ; NY; OR; PA; RI; SC; TX; VA; NB; NF; NS; PE; QC; coastal areas of Europe; n Africa; sw Asia [Introduced and naturalized in other coastal regions]
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almost worldwide; Mediterranean region; arid and coastal zones of Eurasia; n Africa; e Africa; s Africa [Introduced in North America] |
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Discussion | Subspecies ca. 2 (2 in the flora). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Species ca. 130 (6 in the flora). In this treatment, a rather broad and traditional generic concept is accepted for Salsola, including Caroxylon and other segregate genera. It is evident that Salsola in the traditional sense should be regarded as a group of genera rather than a natural monophyletic genus. V. I. Pyankov et al. (2001) recently discussed phylogenetic relationships inferred from parsimony analysis of nucleotide sequences of the internal transcribed spacer regions (ITS) of the 18S–26S nuclear ribosomal DNA of 34 species of Salsola and related genera (Halothamnus Jaubert & Spach, Climacoptera Botschantzev, Girgensohnia Bunge, Halocharis Moquin-Tandon, and Haloxylon Bunge) and four species from representative outgroups (tribes Camphorosmeae and Atripliceae). The study confirmed that Salsola sensu lato is polyphyletic, with several currently recognized related genera rooted within the group. Results of the V. I. Pyankov et al. study also contradict V. P. Botschantzev’s (1969) hypothesis of a South African origin of Salsola sensu lato and place the “cradle” of the genus in central Asia. A comparative taxonomic and phytogeographic analysis (S. L. Mosyakin 2002) also suggests the place of origin of the Salsola generic aggregate is somewhere in the Tethyan region of south-central Asia (probably northern coasts of the ancient Tethys, or adjacent inland lacustrine habitats). Almost all North American taxa belong to Salsola sensu stricto. Species of Salsola sect. Caroxylon (Thunberg) Fenzl, which is represented in North America only by the introduced S. vermiculata, may be recognized in the distinct genus Caroxylon Thunberg following a comprehensive study of the group worldwide. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 4, p. 400. | FNA vol. 4. | ||||||||||||||||||||||||||||
Parent taxa | Chenopodiaceae > Salsola | Chenopodiaceae | ||||||||||||||||||||||||||||
Sibling taxa | ||||||||||||||||||||||||||||||
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Name authority | Linnaeus: Sp. Pl. 1: 222. (1753) | Linnaeus: Sp. Pl. 1: 222. (1753): Gen. Pl. ed. 5, 104. (1754) | ||||||||||||||||||||||||||||
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