View source for Psilostrophe

{{Treatment/ID
|accepted_name=Psilostrophe
|accepted_authority=de Candolle in A. P. de Candolle and A. L. P. de Candolle
|publications={{Treatment/Publication
|title=in A. P. de Candolle and A. L. P. de Candolle, Prodr.
|place=7: 261. 1838
|year=1838
}}
|basionyms=
|synonyms=
|hierarchy=Asteraceae;Asteraceae tribe Heliantheae;Asteraceae (tribe Heliantheae) subtribe Gaillardiinae;Psilostrophe
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Asteraceae]]</div><div class="higher-taxon"><small>tribe</small>[[Asteraceae tribe Heliantheae]]</div><div class="higher-taxon"><small>subtribe</small>[[Asteraceae (tribe Heliantheae) subtribe Gaillardiinae]]</div><div class="higher-taxon"><small>genus</small>[[Psilostrophe]]</div></div>
|etymology=Greek psilo- , bare, and strophe, turn; perhaps alluding to epaleate receptacles, which differ from paleate receptacles in Parthenium, to which de Candolle compared Psilostrophe
|volume=Volume 21
|mention_page=page 415, 416
|treatment_page=page 453
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Biennials,</b> perennials, subshrubs, or shrubs (rarely flowering first year), 8–60+ cm. <b>Stems</b> erect to spreading, branched from bases or throughout (not scapiform). <b>Leaves</b> basal and cauline or all cauline; alternate; petiolate or sessile; blades spatulate to oblanceolate or linear, margins usually entire (sometimes toothed or lobed on larger rosette leaves), faces densely to sparsely arachno-villous or ± strigillose, often gland-dotted as well. <b>Heads</b> radiate, usually in compact, corymbiform arrays or glomerulate clusters (borne singly in <i>P. cooperi</i>). <b>Involucres</b> cylindric to campanulate or obconic, 2–7 mm diam. <b>Phyllaries</b> persistent, 5–12 in 1–2 series (erect in fruit, distinct, oblong to lanceolate, bases ± indurate). <b>Receptacles</b> flat or convex, smooth or ± pitted (without setiform enations, sometimes gland-dotted), epaleate. <b>Ray</b> florets 1–8, pistillate, fertile; corollas yellow to orange (marcescent, spreading or reflexed in fruit). <b>Disc</b> florets 5–25+, bisexual, fertile; corollas yellow to orange, tubes shorter than narrowly cylindric throats, lobes 5, deltate (equal, papillate abaxially). <b>Cypselae</b> cylindric to clavate or obpyramidal, sometimes weakly obcompressed (ray), all striate-ribbed, usually glabrous, sometimes gland-dotted (villous in <i>P. gnaphalodes</i>, sometimes hirtellous in <i>P. tagetina</i>); pappi of 4–8 ± oblong or elliptic to lanceolate or lance-subulate, entire (lacerate in <i>P. gnaphalodes</i>) scales (without prominent midribs). <b>x</b> = 16.</span><!--

-->{{Treatment/Body
|distribution=United States;Mexico.
|discussion=<p>Species 7 (6 in the flora).</p><!--
--><p>My treatment of psilostrophes closely follows that by R. C. Brown (1978). <i>Psilostrophe</i> mexicana R. C. Brown is known from Chihuahua and Durango.</p>
|tables=
|references={{Treatment/Reference
|id=brown1978a
|text=Brown, R. C. 1978. Biosystematics of Psilostrophe (Compositae: Helenieae). II. Artificial hybridization and systematic treatment. Madroño 25: 187–201.
}}{{Treatment/Reference
|id=turner1988a
|text=Turner, B. L., M. W. Turner, and J. C. Crutchfield. 1988. Populational analyses and new combinations in Psilostrophe tagetina and P. gnaphalodes (Asteraceae, Heliantheae). Phytologia 65: 231–240.
}}
}}<!--

--><div class="treatment-key">
==Key==
<div class="treatment-key-group">
  
{| class="wikitable fna-keytable"
|-id=key-0-1
|1
|Subshrubs or shrubs; stems pannose (white); heads borne singly; peduncles 35–60(–80+) mm
|[[Psilostrophe cooperi|Psilostrophe cooperi]]
|-id=key-0-1
|1
|Biennials or perennials; stems arachno-villous (gray to gray-green) or strigillose (greenish); heads in corymbiform arrays; peduncles 0.5–25(–50) mm
|[[#key-0-2| > 2]]
|-id=key-0-2
|2
|Stems ± strigillose, (greenish, sometimes ± villous in proximal axils); ray laminaereflexed in fruit
|[[Psilostrophe sparsiflora|Psilostrophe sparsiflora]]
|-id=key-0-2
|2
|Stems mostly arachno-villous (gray to gray-green); ray laminae spreading in fruit
|[[#key-0-3| > 3]]
|-id=key-0-3
|3
|Involucres 7–9(–12) mm; disc florets (10–)12–15(–20); pappus scales oblong to ovate, 1.5–2 mm
|[[Psilostrophe bakeri|Psilostrophe bakeri]]
|-id=key-0-3
|3
|Involucres 4–6(–8) mm; disc florets 5–8(–12); pappus scales elliptic or lanceolate to linear-subulate, 2–3+ mm
|[[#key-0-4| > 4]]
|-id=key-0-4
|4
|Cypselae villous
|[[Psilostrophe gnaphalodes|Psilostrophe gnaphalodes]]
|-id=key-0-4
|4
|Cypselae usually glabrous, sometimes hirtellous and/or gland-dotted
|[[#key-0-5| > 5]]
|-id=key-0-5
|5
|Peduncles (3–)12–20(–40) mm; ray laminae (5–)7–14+ mm
|[[Psilostrophe tagetina|Psilostrophe tagetina]]
|-id=key-0-5
|5
|Peduncles (0.5–)1–3(–5+) mm; ray laminae 3–4(–6) mm
|[[Psilostrophe villosa|Psilostrophe villosa]]
|}
</div></div><!--

-->{{#Taxon:
name=Psilostrophe
|author=John L. Strother
|authority=de Candolle in A. P. de Candolle and A. L. P. de Candolle
|rank=genus
|parent rank=subtribe
|synonyms=
|basionyms=
|family=Asteraceae
|distribution=United States;Mexico.
|reference=brown1978a;turner1988a
|publication title=in A. P. de Candolle and A. L. P. de Candolle, Prodr.
|publication year=1838
|special status=
|source xml=https://jpend@bitbucket.org/aafc-mbb/fna-data-curation.git/src/f50eec43f223ca0e34566be0b046453a0960e173/coarse_grained_fna_xml/V19-20-21/V21_1138.xml
|tribe=Asteraceae tribe Heliantheae
|subtribe=Asteraceae (tribe Heliantheae) subtribe Gaillardiinae
|genus=Psilostrophe
}}<!--

-->[[Category:Treatment]][[Category:Asteraceae (tribe Heliantheae) subtribe Gaillardiinae]]