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Pterostegia drymarioides

Higher Taxonomy
Family: PolygonaceaeView DescriptionDichotomous Key

Habit: Annual to shrub [tree]. Stem: nodes swollen or not. Leaf: simple, basal or cauline, generally alternate; ocreae present or 0, generally scarious, persistent or not. Inflorescence: flower clusters in axillary to terminal cyme-, panicle-, raceme-, spike-, umbel- or head-like arrangements, entire inflorescence or main inflorescence branches generally subtended by bracts ("inflorescence bracts"); peduncles present or 0; flower clusters in Eriogoneae-Eriogonoideae subtended by involucre of >= 1 free or +- fused, sometimes awn-tipped bracts ("involucre bracts") or, in Polygonoideae and rarely in Eriogonoideae, not (if bracts completely fused, involucre "tubular"); pedicels in Eriogoneae each often subtended by 2 free, transparent, linear bractlets or in Polygonoideae all subtended by 2+ fused, membranous, wide bractlets. Flower: generally bisexual, small, 1--200 per node; perianth parts 2--6, generally in 2 whorls, free or basally fused, generally petal-like, often +- concave adaxially, often darker at midvein, often turning +- red or +- brown in age; stamens [1]3 or 6--9 in 2 whorls; ovary superior, 1-chambered, ovule 1, styles 1--3. Fruit: achenes, included in or exserted from perianth, generally 3-angled, ovoid or elliptic, generally glabrous.
Genera In Family: 48 genera, +- 1200 species: worldwide, especially northern temperate; some cultivated for food (Coccoloba, sea-grape; Fagopyrum, Rheum, Rumex) or ornamental (Antigonon, lovechain; Coccoloba; Muehlenbeckia; Persicaria; Polygonum), a few timbered (Coccoloba; Triplaris). Several (Emex; Fallopia; Persicaria; Polygonum; Rumex) are weeds. Note: Treatment of genera in Eriogonoideae based on monographic work of James L. Reveal. Involucre number throughout is number (1--many) per ultimate grouping, at tips of ultimate branches; flower number is per flower cluster or involucre, unless otherwise stated. Fagopyrum esculentum Moench not naturalized, considered an historical waif (or garden weed +- presently), therefore not treated.
eFlora Treatment Author: Mihai Costea, except as noted
Genus: PterostegiaView Description 


Species In Genus: 1 sp. Etymology: (Greek: wing covering, for winged bract)
eFlora Treatment Author: James L. Reveal & Thomas J. Rosatti

Pterostegia drymarioides Fisch. & C.A. Mey.
Habit: Annual, generally sprawling, 0.1--10(12) dm diam, hairy. Leaf: cauline, opposite; blades entire or generally lobed, wide, 0.3--2 cm, 0.5--2.5(3) cm wide, awns 0; ocreae 0. Inflorescence: terminal, cyme-like; peduncles 0; involucre bract erect, 2-winged, swollen on 1 side, veined, 1--1.5(3) mm, (1.5)2--3(3.5) mm wide, awns 0. Flower: 2--3, 0.9--1.2 mm, hairy; perianth pale yellow to pink or rose, lobes (5)6, entire; stamens 6. Fruit: 1.2--1.5 mm, obconic, winged, glabrous, generally brown; embryo straight. Chromosomes: n=14.
Ecology: Common. Sand or gravel; Elevation: < 1600 m. Bioregional Distribution: CA; Distribution Outside California: to southern Oregon, southwestern Utah, western Arizona, northwestern Mexico. Flowering Time: Mar--Jul
Synonyms: Pterostegia diphylla Nutt.; Pterostegia diphylla Nutt. var. biloba Nutt.; Pterostegia microphylla Nutt.
eFlora Treatment Author: James L. Reveal & Thomas J. Rosatti
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botanical illustration including Pterostegia drymarioides


Citation for this treatment: James L. Reveal & Thomas J. Rosatti 2016. Pterostegia drymarioides, in Jepson Flora Project (eds.) Jepson eFlora,, accessed on October 26, 2016.

Citation for the whole project: Jepson Flora Project (eds.) 2016. Jepson eFlora,, accessed on October 26, 2016.

Pterostegia drymarioides
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© 2013 Keir Morse
Pterostegia drymarioides
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© 2009 Keir Morse
Pterostegia drymarioides
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© 2008 Steve Matson
Pterostegia drymarioides
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© 2005 James M. Andre
Pterostegia drymarioides
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© 2013 Keir Morse
Pterostegia drymarioides
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© 2016 Michael Charters

More photos of Pterostegia drymarioides in CalPhotos

Geographic subdivisions for Pterostegia drymarioides:
Markers link to CCH specimen records. Yellow markers indicate records that may provide evidence for eFlora range revision or may have georeferencing or identification issues. Purple markers indicate specimens collected from a garden, greenhouse, or other non-wild location.
map of distribution 1
(Note: any qualifiers in the taxon distribution description, such as 'northern', 'southern', 'adjacent' etc., are not reflected in the map above, and in some cases indication of a taxon in a subdivision is based on a single collection or author-verified occurence).

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Data provided by the participants of the Consortium of California Herbaria.
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CCH collections by month

Duplicates counted once; synonyms included.
Species do not include records of infraspecific taxa.
Blue line denotes eFlora flowering time.