Cerastium texanum |
Cerastium brachypodum |
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Chihuahuan mouse-ear chickweed, Texas chickweed, Texas mouse-ear chickweed |
bractpod chickweed, mouse-ear chickweed, short-stalk mouse-ear chickweed, shortstalk chickweed |
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Habit | Plants annual, with slender taproot and branched caudex. | Plants annual, with filiform tap-root. |
Stems | erect, sparingly branched proximally, slender, 15–35 cm, sparsely glandular-pilose; small axillary tufts of leaves absent. |
erect, simple or several from branched caudex, 5–20 cm, glandular-pubescent, nodes without long, wooly hairs; small axillary tufts of leaves absent. |
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. |
sessile, not marcescent, usually confined to proximal 1/2 of plant; mid-stem leaves with blade lanceolate to narrowly elliptic or oblanceolate, 5–30 × 2–8 mm, apex ± acute, usually rather sparsely, softly pubescent; proximal leaves sometimes forming loose rosette, blade ovate to obovate or spatulate, apex ± obtuse. |
Inflorescences | very open and loose, 2–9(–25)-flowered cymes; bracts narrowly lanceolate, pilose. |
compact to open, dichotomous, 3–30-flowered cymes, confined to distal portion of stem; bracts herbaceous, lanceolate, glandular-puberulent. |
Pedicels | straight, becoming sharply deflexed at base, slender, 5–20 mm, elongating in fruit, 1.5–4 times as long as sepals, glandular-pilose. |
often becoming deflexed at base, 3–10(–12) mm, 0.5–1.25 times as long as sepals in flower, elongating to equaling capsule, glandular-pubescent. |
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 broadly lanceolate, 3–4.5 mm, apex subacute, glandular-puberulent to glabrate, hairs shorter than sepal tip, outer sepals herbaceous or with narrow margins, inner with broad margins; petals ovate-elliptic, 3–4 mm, equaling or shorter than sepals, apex 2-fid; stamens 10; styles 5. |
Capsules | cylindric, straight, 5–12 mm, 1.5–2 times as long as sepals; teeth 10, becoming outwardly coiled. |
cylindric, curved, 6–12 mm, 2–2.25 times as long as sepals; teeth 10, erect, margins convolute. |
Seeds | red-brown, 0.4–0.7 mm diam., tuberculate; tubercles ± pointed; testa not inflated. |
golden brown, 0.4–0.7 mm diam., tuberculate, especially around edge; testa not inflated. |
2n | = 36. |
= 34. |
Cerastium texanum |
Cerastium brachypodum |
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Phenology | Flowering spring. | Flowering spring and early summer. |
Habitat | Canyons, sandy washes, oak woodlands, mountain pine forests | Grasslands, fields, meadows, open woods, roadsides, waste places, often in seasonally wet rocky or sandy ground |
Elevation | 1200-2800 m (3900-9200 ft) | 100-2700 m (300-8900 ft) |
Distribution |
AZ; NM; Mexico
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AL; AR; AZ; CO; GA; IA; ID; IL; IN; KS; LA; MI; MO; MT; ND; NE; NM; NV; OK; OR; SC; SD; TN; TX; UT; VA; WI; WY; AB; MB; ON; SK; Mexico
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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.) |
Cerastium brachypodum differs from C. nutans in its smaller size; its short pedicels, which often become deflexed at the base instead of near the capsule; and its pubescence, which is usually sparser and lacks any long, lanate hairs. However, some specimens from the arid region of the southwest have a dense gray pubescence. Plants from the Arizona desert, which have particularly long and narrow capsules, are the basis for the erroneous report of C. gracile Dufour from that region. Cerastium fastigiatum can be very similar to C. brachypodum but differs in its longer pedicels, narrowly acute leaves, glandular pubescence on the stems, and much more branched (fastigiate) habit. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 5, p. 90. | FNA vol. 5, p. 83. |
Parent taxa | Caryophyllaceae > subfam. Alsinoideae > Cerastium | Caryophyllaceae > subfam. Alsinoideae > Cerastium |
Sibling taxa | ||
Synonyms | C. longepedunculatum var. sordidum, C. sordidum, Stellaria montana | C. nutans var. brachypodum, C. adsurgens, C. brachypodum var. compactum |
Name authority | Britton: Bull. Torrey Bot. Club 15: 97. (1888) | (Engelm. ex A. Gray) B. L. Rob.: Mem. Torrey Bot. Club 5(Sig. 10): 150. 27 Apr (1894) |
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