Astragalus douglasii (Torr. & A. Gray) A. Gray,, 1864

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

21. Astragalus douglasii (Torr. & A. Gray) A. Gray, Proc. Amer. Acad. Arts 6: 215. 1864

Phaca douglasii Torr. & A. Gray , Fl. N. Amer. 1(2): 346. 1838; Tragacantha douglasii (Torr. & A. Gray) Kuntze , Revis. Gen. Pl. 2: 944. 1891.

Astragalus tejonensis M. E. Jones, Proc. Calif. Acad. Sci. , ser. 2, 5(18): 644–645. 1895; Astragalus douglasii var. tejonensis (M. E. Jones) M. E. Jones, Contrib. W. Bot. 10: 61. 1902; Phaca tejonensis (M. E. Jones) A. Heller, Muhlenbergia 2(18): 85. 1905.

Phaca vallicola Rydb., N. Amer. Fl. 24(6): 343. 1929.

Phaca megalophysa Rydb. , 24(6): 344–345. 1929.— Astragalus douglasii (Torr. & A. Gray) A. Gray var. megalophysa (Rydb.) Munz & McBurney, Bull. S. Calif. Acad. Sci. 31(2): 65. 1932.

Perennial. Stems up to 1 m long, erect, suberect, decumbent or postrate but ascending distally, occasionally branched from the base; pubescence scattered or dense, middle an upper parts with trichomes up to 0.6 mm long, straight or somewhat appressed, glabrate o almost so basally. Stipules 1.4–6.6 mm long, lanceolate to triangular, semi or completely clasping, not connate. Leaves 5–18 cm long; leaflets 7–25, 5–34 mm long, linear, oblong, oblanceolate, obtuse, truncate to retuse, mucronate, rarely acute, dorsally carinate, with evident midrib, glabrous in both surfaces or glabrous adaxially only and pubescent abaxially, pubescent in both faces, but always denser adaxially, the pairs frequently distant to each other. Peduncles 2.3–13.5 cm long; the racemes up to 17 cm, flowers 8–38 ascendant or spreading. Flowers white-yellowish (ochroleucos), green-white to yellowish, greenish-yellow, dull yellow (reddish in bud)*, immaculate; the calyx 4–8 × 2.5–3.6 mm, papery, the tube campanulate to ovoid, 2.4–4.2 mm, scarce to dense strigose, invested with white or rarely and completely with black ones, the teeth 0.9–4 mm long, triangular to subulate; the banner 6.3–13.3 × 6–10.3 mm, recurved; the wings 5–11.7 × 7.9–10.9 mm, the claw 2.4–4.2 mm long, obtuse, obovate; the keel 6.2–11 × 2.3–3 mm, the claw 2.3–4.4 mm long, the blade 4.7–6 mm long, triangular, incurved. Pod 2.4–6 × 1.2–3.5 cm, spreading or humistrate when fruits ripen, regularly sessile, rarely tiny but imperceptibly elevated in the receptacule, inflated bladder-shape, elliptic, straight, basally rounded, dorsally gibous-convex, ventrally convexed, distally abruptly contracted in a short flattened, incurved, 2–8 mm long beak, the valves thin, light-green, light-brown or with purple spots, strigose, glabrate or subglabrate, lustrous; ovules 22–78; seeds 2.3–3 mm long, brown to reddish-brown.

Distribution:— In Mexico restricted to Baja California, from La Rumorosa, Sierra Juárez, Sierra San Pedro Mártir to Cataviña. Also, in California ( USA).

Comments:— Morphologically, the three varieties are quite similar, but they can can be discerned based on the type of pubescence on pod and stems growth habit.

1. Ovary and pod glabrate; ovules 36 or less............................................................................................................... var. glaberriumus

- Ovary and pod strigose, rarely glabrous, if glabrous, ovules 40 or more...........................................................................................2

2. Stems and peduncles erect; pods no humistrate ........................................................................................................... var. perstrictus

- Stem diffuse; peduncles incurved, distally ascendant; pod humistrate ............................................................................ var. parishii