Cerastium texanum |
Cerastium semidecandrum |
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Chihuahuan mouse-ear chickweed, Texas chickweed, Texas mouse-ear chickweed |
five-stamen chickweed, five-stamen mouse-ear chickweed, five-stamen mouse-ear chikweed, little chickweed |
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Habit | Plants annual, with slender taproot and branched caudex. | Plants annual, with slender taproot. |
Stems | erect, sparingly branched proximally, slender, 15–35 cm, sparsely glandular-pilose; small axillary tufts of leaves absent. |
erect or ascending, branching at base, 1–20 cm, viscid, covered with short, dense, glandular and eglandular hairs; short 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. |
not marcescent, sessile but proximal leaves often spatulate; blade 5–18 × 2–5 mm, covered with short, white hairs; basal leaves with blade narrowly oblanceolate and ± spatulate, apex obtuse; cauline with blades ovate to elliptic-oblong, apex obtuse to acute. |
Inflorescences | very open and loose, 2–9(–25)-flowered cymes; bracts narrowly lanceolate, pilose. |
open, 3–30-flowered cymes; bracts lanceolate, with broad, scarious margins, glandular-pubescent. |
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 at apex, often sharply angled at base, 3–8(–12) mm, 1–3 times as long as capsule, densely glandular-pubescent and viscid. |
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, 3–5 mm, margins broad, apex acute, glandular-pubescent; petals with unbranched veins, oblanceolate, 2–3 mm, shorter than sepals, apex notched; stamens 5; styles 5. |
Capsules | cylindric, straight, 5–12 mm, 1.5–2 times as long as sepals; teeth 10, becoming outwardly coiled. |
cylindric, slightly curved, 4.5–6.5 mm, 1.5–2 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. |
pale yellowish brown, 0.4–0.6 mm, finely tuberculate; testa not inflated. |
2n | = 36. |
= 36. |
Cerastium texanum |
Cerastium semidecandrum |
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Phenology | Flowering spring. | Flowering spring. |
Habitat | Canyons, sandy washes, oak woodlands, mountain pine forests | Common weed in dry, sandy, and gravelly places, roadsides and footpaths, parking lots, dunes |
Elevation | 1200-2800 m (3900-9200 ft) | 0-300 m (0-1000 ft) |
Distribution |
AZ; NM; Mexico
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AR; CT; FL; GA; ID; IL; IN; KS; LA; MA; MD; MI; MO; NC; NE; NJ; NY; OH; OR; PA; RI; SC; WA; WI; BC; NS; ON; Eurasia [Introduced in North America]
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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.) |
The very broad, scarious margins of the sepals and bracts distinguish this small, ephemeral species. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 5, p. 90. | FNA vol. 5, p. 90. |
Parent taxa | Caryophyllaceae > subfam. Alsinoideae > Cerastium | Caryophyllaceae > subfam. Alsinoideae > Cerastium |
Sibling 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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