Monographs Details: Astragalus tephrodes var. eurylobus Barneby
Authors:Rupert C. Barneby
Authority: Barneby, Rupert C. 1964. Atlas of North American Astragalus. Mem. New York Bot. Gard. 13(2): 597-1188.
Description:Latin Diagnosis - statura valde robusta, legumine maximo latissimo, ovulis magis numerosis, et seminibus majoribus (ut jam supra in clave diagnostica notatis) a caeteris speciei formis absimilis.
Variety Description - Relatively coarse and robust, the herbage canescently pilosulous with sinuous and a few straight, ascending hairs up to 0.55—0.9 mm. long, the leaflets equally pubescent on both sides; stems angular, 2-9 cm. long; stipules 3-8 mm. long, all but the lowest pilosulous dorsally; leaves (7) 10-24 cm. long, with (19) 21—27 rhombic-obovate, broadly elliptic, or oblanceolate, obtuse or emarginate, flat leaflets 7-27 mm. long; peduncles 10-18 cm. long; racemes 18-26-flowered, the axis (2.5) 3.5—14 cm. long in fruit; calyx 10.8—12.2 mm. long, the cylindric tube 9-10.1 mm. long, 3.9-4.4 mm. in diameter, the teeth 1.8-2 mm. long; banner 19—21.8 mm., wings 19—20.8 mm., keel 17—19 mm. long; pod broadly oblong-ellipsoid, (2.3) 2.5—4 cm. long, 1—1.6 cm. in diameter, the beak 5-10 mm. long, the rigid, subligneous valves becoming strongly rugulose, densely strigulose.
Distribution and Ecology - On saddles and along gullied draws in low alkaline sandy-clay hills, 4650-4950 feet, locally abundant in the Needle Mountains, northeast of Caliente, Lincoln County, Nevada.-Map. No. 81.-April to June.
Discussion:The surface topography of a great part of Lincoln County, Nevada, is sculptured out of calcareous bedrock, but the Needle Mountains are an exception, being raised on a pediment of soft, readily weathered pink sandstone which has broken down into an extensive area of sandy badlands. The var. eurylobus is locally plentiful on this formation and apparently confined to it The variety is distinguished from var. brachylobus by its exceptionally large, pluriovulate pods, massive seeds, and canescently pilosulous foliage. The var. brachylobus is known to occur north of the Colorado River only in the upper Virgin Valley in southwestern Utah (Springdale, Jones in 1894, POM), but the specimens from this locality are as yet very meager and the station itself requires confirmation.
Nevada United States of America North America