Astragalus nuttallianus DC. var. imperfectus (Rydb.) Barneby, Leafl.

Castillón, Eduardo Estrada, Quintanilla, José Ángel Villarreal, Delgado-Salinas, Alfonso & Rebman, Jon P., 2023, The genus Astragalus (Leguminosae: Papilionoideae: Galegeae) in Mexico, Phytotaxa 586 (1), pp. 1921-1935 : 1921-1935

62.3. Astragalus nuttallianus DC. var. imperfectus (Rydb.) Barneby, Leafl. West. Bot. 3: 1009. 1942

Type:— USA, Nevada, Nye County, Rhyolite , 17 May 1909, Heller 9637 (holotype (based on Hamosa imperfecta ) NY00011921!; isotype: RENO 009575 digital image!, PH 00013580 digital image!) .

Hamosa imperfecta Rydb., Bull. Torrey Bot. Club 54: 329. 1927.

Leaflets elliptic, none retuse; calyx teeth short, 1–2 mm long; the tube 1.9–2.8 mm long, the trichomes appressed o slightly ascendant, up to 0.8 mm long.

Distribution:— Northwestern Mexico, Baja California in northeastern (Cucupa Mts.), at El Mármol, 12 km N to Santa Ynés Ranch (29°53’N – 114°51’W); in Sonora, isolated at the northwestern, adjacent to the Pinacate Volcano (31°46’N – 113°26’W) and isolated also in San Carlos Bay (27°58’N – 111° 04’W). Also, in Colorado, Utah, California, and Arizona ( USA) ( Fig. 19 ).

Habitat:— Adjacent to coastal dunes; gravel soils; bottom of canyons; stony plains; alluvial plains; desert scrubland; 1–420 m.

Specimens examined:— BAJA CALIFORNIA: 18 April 1905, Crater, Arrobrito, Cucapa Mts., D. MacDougal 203 ( NY) , 24 February1973, Agua Dulce, R. Moran 20260, J. L. Reveal ( NY) ; SONORA: 15 April 1992, Campo Rojo, east side of Pinacate volcanic field, R. S. Felger 92-481B, S. W. Whitely ( MEXU, NY) ; 15 May 2010, Ánimas Valley , 58.7 km (byr air) E. of Agua Prieta, Cuenca Los Ojos Foundation property, T. R. Van Devender 2010-406, A. L. Reina, C. Roll ( MEXU, USON) ; 23 March 1970, Mpio. Puerto Peñasco, ca. 0.5 km S of Pinacate Peak, Sierra Pinacate, R. S. Felger 19310 ( USON 15 April 1992, Campo Rojo, east side of Pinacate volcanic field, R. S. Felger 92-481B. S. W. Whitely ( MEXU).

Figures

FIGURE 19. Map showing the distribution of Astragalus nuttallianus var. nuttallianus, A. nuttallianus var. austrinus, A. nuttallianus var. cedrosensis, A. nuttallianus var. imperfectus, A. nuttallianus var. trichocarpus, and A. nuttallianus var. zapatanus in Mexico.