19.2 Astragalus didymocarpus Hook. var. dispermus (A. Gray) Jeps., Fl. Calif. 2(4): 376–377. 1936

Type:— USA, Arizona, Wickenburg, Palmer 2 1876 (holotype: GH 00058717 digital image!

Astragalus dispermus A. Gray, Proc.Amer.Acad.Arts 13: 365–366. 1878.— Hesperastragalus dispermus (A. Gray) A.Heller, Muhlenbergia 1(8): 137. 1906.— Astragalus dispermus A. Gray var. albus L. E. James, Contr. Duddl. Herb. 4(4): 68. 1951.

Characteristics as in the key. Sometimes the teeth red or red-purple, contrasting with the white trichomes.

Distribution:— From La Rumorosa and Sierra Juárez to the lower parts and middle atitudes in the sierra San Pedro Martir to Cataviña. Barneby (1964) report this species from southern from Arizona bordering Sonora, but. There is no available herbarium material to ensure that the variety is distributed in Sonora, although we can presume that the proximity in Arizona could extend to Sonora (Fig. 5).

Habitat:— Sandy, clayey, gravel and granitic soils; boulder fields; stony slopes and alluvial fans; soils with exposed parental rock; in intermittent streams; in different associations of desert scrubland with creosote bush, mezquite, maguey, cirio, columnar cacti, jojoba; chaparral communities and juniper-pine forest; also in burned or thinned areas, 610–2000 m.

Comments:— From the three varieties of this species, this is the one with the widest distribution in Baja California.

Specimens examined:—BAJA CALIFORNIA: 3 April 1998, Cataviña boulder fields: ca. 5 miles N of Cataviña and 0.6 miles west of Hwy. 1, J. Rebman 4993 (BCEMX, CAS, SD); 10 May 1991, 9 miles south of Rte. 3 on road to Mike’s Sky Ranch and Parque Nacional Sierra San Pedro Martir, J. P. Rebman 1087, K. Rice (NY); 28 April 1978, Rd to El Alamo ca. 53 mi SE of Ensenada, w side of Sierra Juarez, C. Cagle 2720, B. Ertter, C.R. Broome (NY); 8 May 1985, S of La Rumorosa: 3 km S of La Rumorosa, Ejido Gustavo R. V. Centro Recreativo Familiar, R. F. Thorne 60442, W. Wisura (NY); 9 May 1985, S of El Condor: 0.5–2.3 miles south, R. F. Thorne 60600, W. Wisura (BCMEX, NY); 29 March 1985, Along the old dirt peninsular highway, parallel to Hwy 1, 5.5–6.6 mi. north of Catavina, A. C. Sanders 5480, E. Rodríguez, J. West et al. (NY); 15 May 1977, Sierra Juázez, 5 km W of La Rumorosa, R. Moran 24075 (CAS); 14 May 1948, One-year-old burned over granitic hillsides 16 miles southeast of Tecate, I. L. Wiggins 11821 (CAS); 12 May 1941, In granitic soil on hillside at Los Emes southern part of Sierra San Pedro Martir, I. L. Wiggins 9890 (CAS, US); 22 April 1962, 1.5–2.5 miles upstream from Rincon, 4.5 miles northeast of Santa Catarina, 64 miles southeast of Ensenada, R. E. Broder 726 (CAS, MEXU, US); 21 April 1962, R. E. Broder 653 (CAS); 5 April 1973, 15 miles S of San Agustin., H. Gentry 2315, B. Gentry (US); 10 April 1931, Rosario Wash., I. L. Wiggins 5245 (TEX-LL, US); 18 May 1986, Ensenada, G. A. Levin 1690, C. Brey, R. P. Levin (MEXU, SD); 16 March 1963, Rancho las Lagunitas, near the pond, R. Moran 126911/2 (CAS, SD); 21 April 2004, Sierra La Asamblea: northeast of El Crucero (junction of Hwy. 1 & the road to Bahia de Los Angeles), granitic mountains NW of Rancho San Luis; red clay/granitic flats along the trail between the ranch and the camp called Datilillo J. Rebman 9911, M. Salazar, H. Riemann, B. Vinton (SD); 20 March 2010, 24 km NW by air from turn off of Highway 1 to Bahia de los Angeles., B. T. Wilder 10-140, J. Rebman, I. A. Happle, S. I. Enciso (SD).