Cerastium texanum |
Cerastium arvense |
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Chihuahuan mouse-ear chickweed, Texas chickweed, Texas mouse-ear chickweed |
céraiste des champs, field chickweed, field mouse-ear chickweed, field or prairie mouse-ear chickweed, meadow chickweed, starry cerastium |
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Habit | Plants annual, with slender taproot and branched caudex. | Plants perennial, clumped and taprooted, or mat-forming and long-creeping rhizomatous. | ||||
Stems | erect, sparingly branched proximally, slender, 15–35 cm, sparsely glandular-pilose; small axillary tufts of leaves absent. |
flowering shoots often decumbent proximally, 5–20(–30) cm, glandular-pubescent distally, pilose-subglabrous, deflexed or spreading proximally; non-flowering shoots present; small tufts of leaves present in axils of proximal leaves. |
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Leaves | not marcescent; proximal blades broadly spatulate-petiolate, 8–55 × 3–16 mm, apex acute or obtuse, sometimes short-acuminate, softly pilose; cauline few, sessile, blade linear-lanceolate to narrowly oblanceolate, 7–30 mm, apex acute, pilose. |
not marcescent, sessile, ± spatulate proximally; blade linear-lanceolate to lanceolate or narrowly oblong, 4–30 × 0.5–6 mm, apex acute, rarely obtuse, subglabrous to softly pubescent, sometimes glandular. |
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Inflorescences | very open and loose, 2–9(–25)-flowered cymes; bracts narrowly lanceolate, pilose. |
lax, 1–20-flowered cymes, pubescence short, glandular; bracts lanceolate, margins narrow, scarious, glandular-pubescent. |
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Pedicels | straight, becoming sharply deflexed at base, slender, 5–20 mm, elongating in fruit, 1.5–4 times as long as sepals, glandular-pilose. |
curved just below calyx, 5–30 mm, 1–6 times as long as sepals, glandular-pubescent. |
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Flowers | sepals green, turning pale orange-brown in fruit, lanceolate to ovate, 3–6 mm, margins narrow, apex acute, with short, glandular pubescence; petals oblanceolate, 5–8 mm, 1.5–2 times as long as sepals, apex 2-fid; stamens 5; styles 5. |
sepals narrowly lanceolate to lance-elliptic, 3.5–7 mm, margins narrow, softly pubescent; petals obovate, 7.5–12.5 mm, ca. 2 times as long as sepals, apex 2-fid; stamens 10; anthers 0.8–1.1 mm; styles 5. |
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Capsules | cylindric, straight, 5–12 mm, 1.5–2 times as long as sepals; teeth 10, becoming outwardly coiled. |
cylindric, curved, 7.5–11.5 × 2.5–4 mm, (1–)1.5–2 times as long as sepals; teeth 10, erect, margins convolute. |
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Seeds | red-brown, 0.4–0.7 mm diam., tuberculate; tubercles ± pointed; testa not inflated. |
brown, 0.6–1.2 mm diam., tuberculate; testa not inflated. |
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2n | = 36. |
= 36, 72, (108, Europe). |
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Cerastium texanum |
Cerastium arvense |
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Phenology | Flowering spring. | |||||
Habitat | Canyons, sandy washes, oak woodlands, mountain pine forests | |||||
Elevation | 1200-2800 m (3900-9200 ft) | |||||
Distribution |
AZ; NM; Mexico
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AK; AZ; CA; CO; CT; IA; ID; IN; MA; MD; ME; MI; MN; MO; MT; ND; NE; NH; NJ; NM; NV; NY; OH; OR; PA; SD; UT; VA; VT; WA; WI; WV; WY; AB; BC; MB; NB; NF; NS; NT; NU; ON; PE; QC; SK; YT; Worldwide
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Discussion | Cerastium texanum is exceptionally variable in flower and capsule size. The extent to which this variation is due to environmental conditions or is genic in origin is not known. The broad, spatulate basal leaves and the straight, cylindric capsule with its outwardly coiled (revolute) teeth distinguish this species. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Subspecies 2+ (2 in the flora). The infraspecific taxonomy of Cerastium arvense is subject to many different interpretations. While many subspecies have been recognized, the “actual” number is uncertain because of worldwide distribution, wide range of variation, and conflicting taxonomies. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 5, p. 90. | FNA vol. 5, p. 79. | ||||
Parent taxa | Caryophyllaceae > subfam. Alsinoideae > Cerastium | Caryophyllaceae > subfam. Alsinoideae > Cerastium | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | C. longepedunculatum var. sordidum, C. sordidum, Stellaria montana | |||||
Name authority | Britton: Bull. Torrey Bot. Club 15: 97. (1888) | Linnaeus: Sp. Pl. 1: 438. (1753) | ||||
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