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Family: Asteraceae
Roosevelt Dam Rockdaisy
[Laphamia saxicola Eastw.] Images not available |
Perennials or subshrubs, 20-40 cm; glabrate or puberulent. Leaves: petioles 10-30 mm; blades (2-)3-pinnate, 15-55 × 10-50 mm, lobes linear to flat-filiform, scarcely broadened distally. Heads borne singly or (2-4) in loose, corymbiform arrays, 7.5-10 × 10-14 mm. Peduncles 1-3 mm. Involucres broadly campanulate to hemispheric. Phyllaries 14-25, linear-lanceolate to lanceolate, 5-7 × 0.5-1 mm. Ray florets 10-17; corollas yellow, laminae oblong to oblong-ovate, 4-6 × 2-3.2 mm. Disc florets 75-200; corollas yellow, tubes 1-1.2 mm, throats narrowly tubular to narrowly funnelform, 2-2.5 mm, lobes ca. 0.7 mm. Cypselae narrowly oblanceolate to narrowly oblong-elliptic, 2.8-3.2 mm, margins notably calloused, sparsely short-hairy; pappi 0 or of 1(-2) bristles (2-)4-5 mm. 2n = 34. Flowering spring-fall. Crevices of igneous rocks; of conservation concern; 700-1100 m; Ariz. Perityle saxicola occurs in the area of Tonto National Monument and Roosevelt Dam in central Arizona. The 2-3-pinnately dissected leaves with long-linear to flat-filiform lobes distinguish it from the similar P. gilensis with its broader leaf lobes.
FNA 2006, Wiggins 1964, Kearney and Peebles 1969 Duration: Perennial Nativity: Native Lifeform: Subshrub General: Slender, much branched perennial or subshrub, 20-40 cm, glabrate to puberulent, branches frequently hanging pendant on cliff faces, finely striate stems, glabrous just below heads. Leaves: On petioles 10-30 mm, blades 2-3 pinnate, 15-55 mm long by 10-50 mm wide, lobes linear to flat-filiform, apex mostly acute. Flowers: Heads borne singly or 2-4 in loose, corymbiform arrays, about 1 cm tall, 12-15 mm broad at anthesis, on peduncles 1-3 mm; involucres broadly campanulate to hemispheric; phyllaries 14-25, linear-lanceolate to lanceoalte 5-7 mm tall by 0.5-1 mm wide; 10-17 ray florets, yellow corollas, oblong to oblong-ovate, 4-6 mm long by 2-3.2 mm wide; disc florets 75-200, corollas yellow, tubes 1-1.2 mm, throat narrowly tubular to narrowly funnelform. Fruits: Cypselae oblong, dark brown to nearly black, 2.8-3.2 mm, margins notably calloused, sparsely short hairy. Ecology: Found in the crevices of igneous rocks of cliffs from 2,500-4,000 ft (762-1219 m); flowers May-June. Notes: Narrow endemic of serious conservation concern, as it is found only near Tonto NM, from the Sierra Ancha to the Supersitions. The 2-3 pinnately but tightly dissected leaves with long-linear to flat-filiform lobes distinguish it from the similar P. gilensis, which has broader leaf lobes. Take serious care in considering a collection of this species or P. gilensis. Ethnobotany: Unknown Etymology: Perityle comes from Greek peri, around and tyle, a callus, which refers to the thick callused margin of the cypselae, saxicola means growing among rocks. Synonyms: Laphamia saxicola Eastw. Editor: SBuckley, 2010 |
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