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Family: Asteraceae
Loomis' thimblehead
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Annuals or biennials, 30-70 cm. Phyllaries 8(-12), mostly linear to narrowly oblanceolate. Rays 0. Disc florets 10-20; corollas creamy to bright yellow, mostly 4-4.5 mm, lobe lengths 0.3-1 times throats; anthers yellowish. Cypselae 2.5-4+ mm; pappus scales 3-5 mm. 2n = 24. Flowering summer-fall. Open, often disturbed, places; 900-2100 m; Ariz., Calif., Nev. Occurrences of Hymenothrix loomisii in California have been geographically scattered, sporadic, and nonpersistent introductions. FNA 2006, Kearney and Peebles 1969, McDougall 1973 Duration: Annual Nativity: Native Lifeform: Forb/Herb General: Herbaceous annuals, perennials, or biennials, to 70 cm tall, erect to ascending, herbage green, glandular above, slightly pubescent, mostly uniformly leafy to the inflorescence. Leaves: Alternate, dissected, the lobes narrow, 1-2 mm wide, the petioles are incurved-puberulent, the upper leaves reduced, sessile. Flowers: Heads discoid, disk flowers 10-20, cream to white or bright yellow, the corolla lobes about 5, these about as long as the throats, the anthers not or only slightly exserted, these light yellow, involucres 4-6 mm high. Fruits: Achenes black, obpyramidal, 4-5 angled. Pappi of 10-20 lanceolate, hyaline paleae, tipped with small awns. Ecology: Found on mesas, plains, roadsides, and along steams, from 3,500-7,500 ft (1067-2286 m); flowering June-October. Distribution: Arizona, California, Nevada. Notes: Good indicators for this species are the incurved-puberluent petioles and the short lobes of the disk corollas, which are about as long as the throats. Ethnobotany: Unknown Etymology: Hymenothrix comes from Greek hymen, meaning membrane and thrix, bristle, while loomisii is named for Harold Frederick Loomis (1896-1976) an American botanist and horticulturalist. Synonyms: None Editor: LCrumbacher 2011 |
