Sonoran Chinchweed, more...
[Pectis postrata var. cylindrica Fern., more]
Annuals, 1-20 cm (across or high); herbage not scented. Stems prostrate to ascending (often mat-forming, densely leafy distally), puberulent (in decurrent lines or throughout) or glabrate. Leaves (bluish green) linear to linear-oblanceolate or narrowly oblong, 10-30 × 1.5-4 mm, margins with 2-5 pairs of setae 1-2 mm, faces glabrous (abaxial densely dotted with scattered, circular oil-glands 0.05-0.2 mm). Heads borne singly or in congested, (leafy) cymiform arrays. Peduncles 1-5 mm. Involucres cylindric. Phyllaries coherent (falling together), oblong to oblong-obovate, 6-10 × 2-3 mm (dotted with scattered, elliptic oil-glands 0.05-0.15 mm). Ray florets 3(-4); corollas 3-4 mm (scarcely surpassing phyllaries). Disc florets (3-)7-14; corollas 2.2-2.6 mm (2-lipped). Cypselae 4-5.5 mm, puberulent (distally glandular-puberulent); pappi of 2 (ray) and 5 (disc) lanceolate scales 1.5-3.5 mm. 2n = 48. Flowering Jul-Nov. Deserts, oak-juniper woodlands, grasslands, wash channels, mud flats, lawns, roadsides; 700-1500 m; Ariz., N.Mex., Tex.; Mexico (Baja California Sur, Chihuahua, Coahuila, Durango, Nuevo León, Sinaloa, Sonora). Pectis cylindrica (2n = 48) is similar to P. prostrata (2n = 24); the two occasionally grow together (D. J. Keil 1975b). Some herbaria contain mixed collections of the two. No evidence is available of hybrids between the two.
FNA 2006, Kearney and Peebles 1969, McDougall 1973
Duration: Annual Nativity: Native Lifeform: Forb/Herb General: Herbaceous annuals, prostrate to ascending, often mat-forming, much-branched, stems to 30 cm long, pilose along 2 vertical lines or glabrate, herbage not aromatic. Leaves: Opposite, linear to oblanceolate, to 20 mm long and 3 mm wide, faces glabrous, gland-dotted beneath, bluish-green, the margins with 2-5 pairs of bristles 1-2 mm long. Flowers: Heads small, radiate, rays yellow, 3-4, the ligules to 2 mm long, disk flowers 3-7, the corollas 2-lipped, involucres cylindric, to 10 mm long, phyllaries 3, oblong to oblong-ovate, striate, glabrous to pubescent, pale green or yellowish, sparsely gland-dotted, heads subsessile, borne axillary and solitary, inflorescences leafy, often crowded towards branch tips. Fruits: Achenes black, puberulent with silvery, appressed hairs. Pappus of 4-6 narrowly lanceolate scales, each tapering into a slender awn. Ecology: Found on sandy or gravelly soils on plains and mesas, in deserts, oak-juniper woodlands, grasslands, wash channels, mud flats, lawns, and roadsides, from 1,500-5,000 ft (457-1524 m); flowering May-September. Distribution: AZ, s NM, s TX; south to n MEX. Notes: Good identifiers for this species are the prostrate stems with leafy inflorescences, the leaves, inflorescences, and stems gland-dotted, and the 3 phyllaries in a single series. Very similar to P. prostrata but with 3-4 ray florets as opposed to 5. Ethnobotany: Unknown Etymology: Pectis is from the Greek pecteo, to comb, while cylindrica means cylindrical. Synonyms: Pectis postrata var. cylindrica Editor: LCrumbacher 2011, FSCoburn 2015