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  | 1 | 
  Plants dioecious; leaves sessile, mostly opposite [20b.3i. Atriplex subg. Obione subsect. Californicae, for the most part] | 
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  (2) | 
 
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  Plants monoecious; leaves various, but if sessile and mostly opposite, of different distribution | 
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  (3) | 
 
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  | 2 (1) | 
  Leaves 2-5 mm, subequal to internodes; fruiting bracteoles 2-3 mm; coastal or near coastal s Texas and adjacent Mexico | 
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  46 Atriplex matamorensis | 
 
  | + | 
  Leaves 8-25 mm, often surpassing internodes; fruiting bracteoles 4-8 mm; coastal Santa Barbara County, California, Baja California, Mexico | 
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  45 Atriplex watsonii | 
 
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  | 3 (1) | 
  Leaves sessile, blade 5-20 × 1.5-5 mm; fruiting bracteoles 3 mm, rhombic-ovate, acute, sessile, scarcely united, entire; coastal and insular Marin County, California s to Baja California, Mexico [20b.3i. Atriplex subg. Obione subsect. Californicae, in part] | 
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  44 Atriplex californica | 
 
  | + | 
  Leaves subsessile to long petiolate, blade and fruiting bracteoles mostly more than 3 mm, but if shorter, not from coastal California | 
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  (4) | 
 
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  | 4 (3) | 
  Fruiting bracteoles (5-)6-12 mm, fibrous and spongy or merely spongy-thickened | 
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  (5) | 
 
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  Fruiting bracteoles mainly 3-6 mm, not fibrous or spongy thickened | 
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  (7) | 
 
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  | 5 (4) | 
  Fruiting bracteoles obovoid-globular, summit closed by 2 erect, appressed, entire or 3-toothed valves; plants known from cultivation in Wyoming and Texas [20a.4. Atriplex sect. Spongiocarpus, in part] | 
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  15 Atriplex holocarpa | 
 
  | + | 
  Fruiting bracteoles variously shaped, bearing 1 or 2 appendages; different distributions | 
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  (6) | 
 
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  | 6 (5) | 
  Fruiting bracteoles 5-7 mm, broadly ovate in profile, entire or dentate, usually with wartlike projections on faces; sea beaches and coastal strand, occasionally inland, from Humboldt County, California, south to Baja Cali- fornia, Mexico [20b.3h. Atriplex sect. Obione subsect. Leucophyllae] | 
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  43 Atriplex leucophylla | 
 
  | + | 
  Fruiting bracteoles 6-12 mm, broadly turbinate or hemispheric, flattened at summit, bordered by a narrow horizontal wing or acutely angled; plants escaped from cultivation in San Joaquin Valley and San Diego County, California [20a.4. Atriplex sect. Spongiocarpus, in part] | 
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  16 Atriplex lindleyi | 
 
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  | 7 (4) | 
  Seeds dimorphic: black, 1.5-1.7 mm, or brown, 2 mm; bracteoles fleshy; plants low growing, many stemmed; leaf margin irregularly dentate; introduced, sw British Columbia and Washington, to s California, s Arizona, s Nevada, sw Utah, s Arizona, s New Mexico, and Texas [20a.5. Atriplex sect. Semibaccata, in part] | 
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  17 Atriplex semibaccata | 
 
  | + | 
  Seeds monomorphic, either black or brown; bracts not fleshy; plants not low growing; leaf margin entire to dentate; various or other distribution | 
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  (8) | 
 
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  | 8 (7) | 
  Petioles to 1/2 as long as blades, or some blades typically more than 2.5 cm | 
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  (9) | 
 
  | + | 
  Petioles short (much less than 1/2 as long as blades) or lacking, blades of various lengths | 
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  (10) | 
 
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  | 9 (8) | 
  Fruiting bracteoles 3 mm and as wide at apex, bluntly deltoid to circular, swollen, hard, smooth, denticulate at apex, faces unappendaged; Australian species [20a.5. Atriplex sect. Semibaccata, in part, Atriplex muelleri Bentham, see | 
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  17 Atriplex semibaccata] | 
 
  | + | 
  Fruiting bracteoles (3-)5-7 mm, 2-4 mm broad, cuneate-orbicular, margin sharply dentate, faces with appendages or unappendaged; indigenous plants from nc to s California, w and s Nevada, Arizona, New Mexico, w and n Texas, w Oklahoma | 
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  25 Atriplex argentea (in part) | 
 
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  | 10 (8) | 
  Leaves sinuate-dentate; fruiting bracteoles rhombic, widest and 2- to 4-toothed beyond middle; plants known from s California, e to s Utah [20a.5. Atriplex sect. Semibaccata, in part] | 
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  18 Atriplex suberecta (in part) | 
 
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  Leaves variously toothed or entire; fruiting bracteoles variously shaped and toothed; various or other distribution | 
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  (11) | 
 
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  | 11 (10) | 
  Fruiting bracteoles 2-4 mm wide, orbicular, subsessile to short stipitate, strongly compressed, united except at thin margin, margin dentate, terminal teeth often prominent, faces smooth; Mojave and Colorado deserts, California and adjacent s Arizona | 
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  42 Atriplex elegans (in part) | 
 
  | + | 
  Fruiting bracteoles, at least some, more than 4 mm, rhombic or obovate to cuneate-orbiculate, orbiculate, or obovate, margin deeply and acutely dentate, faces variously toothed or appendaged, the terminal teeth not conspicuous; various or other distribution | 
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  (12) | 
 
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  | 12 (11) | 
  Faces of cuneate-orbiculate fruiting bracteoles with 2 dentate crests or covered with irregular, conic-acute, corky tubercles; sandy seashores, s Carolina to s Florida and w to coastal w Texas | 
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  37 Atriplex pentandra (in part) | 
 
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  Faces of obovate or orbiculate fruiting bracteoles without dentate crests or corky tubercles, usually smooth; saline or alkaline substrates in California, Nevada, Arizona, and Utah | 
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  (13) | 
 
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  | 13 (12) | 
  Fruiting bracteoles 2-3 mm, obovate, united 1/2 of length, free margin deeply and sharply dentate, faces smooth or sometimes tuberculate; Santa Barbara and Los Angeles to w San Bernardino Counties, California | 
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  40 Atriplex coulteri | 
 
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  Fruiting bracteoles often larger, suborbiculate, or orbiculate, united except at thin margin, margin dentate, terminal teeth often prominent, faces often smooth; interior California, Nevada, Arizona, and Utah | 
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  (14) | 
 
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  | 14 (13) | 
  Staminate flowers in terminal spikes, pistillate ones in axillary clusters; Sacramento and San Joaquin valleys, California | 
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  41 Atriplex fruticulosa | 
 
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  Staminate flowers in axillary clusters, or staminate and pistillate mixed, usually in axillary clusters; e of Sierra Nevada, in s California, e to Rio Grande Valley of s Texas, and s to Mexico | 
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  42 Atriplex elegans (in part) | 
 
 
 
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