Astragalus idrietorum Barneby, Shreve & Wiggins, Veg. Fl. Sonoran Des.

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

47. Astragalus idrietorum Barneby, Shreve & Wiggins, Veg. Fl. Sonoran Des. 1: 703. 1964

Type:— MEXICO, Baja California, 10 miles s. of El Marmol , 6 March 1930, I. L. Wiggins 4377 (holotype: CAS 0027670 digital image!: isotype: GH 00059420 digital image!, NY 00005804, NA 0095612 digital image!, CAS 0027669 digital image!) .

Perennial, but of short duration. Stems up to 40 cm long, single or branched, decumbent or slightly ascending, strigose, the trichomes up to 0.7 mm long, appressed or sub-appressed. Stipules 2–4.5 mm long, semi-clasping, not connate, triangular. Leaves 3.5–11 cm long; leaflets 11–21, 4–23 mm long, linear, lanceolate, lanceolar-oblong to elliptic, obtuse, mucronate, pubescent in both surfaces, sometimes less dense or glabrate adaxially. Peduncles 3–10 cm long, ascendant; the racemes 2–7.5 cm long, flowers 8–22. Flowers purple, rose-purple, blue-purple, deep or pale violet, violet with the wings lighter, magenta, turning violet when dry; the calyx 3.8–5.2 × 2–2.9 mm, strigose, trichomes white or white and black mixed, the tube 2.4–3.2 mm long, campanulate or with purple tones, the teeth 1.3– 2.2 mm long, subulate to triangular, green to purple; the banner 6.4–9 × 5–7.7 mm, recurved, sometimes in a straight angle (90°), ovate, retuse distally; the wings 5.5–7.9 × 1.8–3.3 mm, the claw 2.2–2.8 mm long, the blade 3.8–4.7 mm long, elliptic to obovate; the keel 5.7–7.4 × 2–2.7 mm, the claw 2.2–3 mm long, the blade 3.8–4.7 mm long, obovate. Pod 1.2–2.2 × 0.6–1.3 cm, ascendant, sessile o minute elevated above the receptacle, ovoid to semi-ovoid, inflated bladder-like, basally rounded or wide turbinate, somewhat asymetric, distally contracted in an 3–5 mm long triangular beak, ventrally shallowly sulcate with a flat filiform suture, dorsally similar, but more convex, the valves strigose, pale green or purple tinted, ochre, lustrous, papery y semi-transparent, septum absent; ovules 8–12; seeds 1.5–2.9 mm long, mitten shape, brown, smooth.

Distribution:— Endemic to the Península of Baja California, distributed in its northernmost part from El Aguajito, San Juan de Dios y El Arenoso, through San Vicente, Misión San Fernando, Ramona, San Pablo, Catarina, Esmeralda and Santa Ynés to Colombia, Codornices, El Crucero y Santa Ana, between coordinates 28°59– 30°N ( Fig. 13 ).

Habitat:— Saline, sandy, rocky and granitic soils; gravelly desert soils; granitic sands; muddy banls along arroyos; sandy washes; roadside and streams; shallow arroyos in rolling plains; boulders and sandy flats and beds; flat gravelly desert; slopes with desert pavement; associated with boojum, columnar cacti, prickl-pear; also in creosote bush - mesquite and mesquite - wolfberry associations; palm canyons; 400–1000 m.

Comments:— The area where this species occurs harbors another seven species of Astragalus such as: A. acutirostris , A. didymocarpus , A. douglasii var. glaberrimus , A. insularis var. harwoodii , A. nuttallianus var. austrinus , A. piscinus and A. fastidius ). But only A. insularis var. harwoodii (racemes with only 3–9 flowers), A. fastidius , A. piscinus , and A. idrietorum , have rose, purple or violet flowers, and also inflated pods (14–50 mm long), from these three species only A. piscinus has stipitate pod. The last two species can be separated based on flower and pod size, and ovules number. A. piscinus has larger petals (banner 10–12.9 mm; wings 9.3–11.5 mm; the keel 8.4–9.1 mm long) and also larger pods (avergaing 23–30 mm long), with almost twice the number of ovules (18–25). Locally common on the roadside.

Specimens examined:—BAJA CALIFORNIA: 3 April 1998, Cataviña cantos rodados; California. 5 millas al N de Cataviña y 5.7 millas al O de la autopista 1 a lo largo del camino a Faro San José., J. Rebman 5009 ( BCMEX; SD) ; 29 March 1985, Along the dirt road to Santa Catarina Landing , 8.5 mi. E of Rancho Sta. Catarina, 9.2 mi. W of Hwy 1 at La Guayaquil, A. C. Sanders 5528, E Rodríguez ( NY) ; 7 November 1947, Southern edge of Llano de Buenos Aires, 11 km southeast of San Augustin on road to Cataviña , A. Carter 1874, A. M. Alexander, L. Kellogg ( JEPS, MEXU, US) ; 30 May 1973, Along the main road about 5 mi. SE of Rancho San Luiz, about 70 mi. SE of Rosario de Arriba , R. & M. Spellenberg 3309, H. Wolf, J. Syvertsen ( ENCB, NY) ; 1 February1973, 7.5 miles south of El Crucero , R. Moran 19627 ( NY, US, SD) ; 9 November 1950, Sandy arroyo 14.6 km. northwest of San Agustin , A. Carter 2793, L. Kellogg ( JEPS, MEXU) ; 16 January 1948, Shallow arroyo on rollig plain, 36 km. south of Cataviná , A. Carter 2547, A. M. Alexander, L. Kellogg ( JEPS, MEXU) ; 2 March 1963, Placer de Cota , at west base of Cerro San Luis, R. Moran 10335, J. Henrickson ( ENCB, NY) ; 18 March 1984, just N of Cataviéa , D. E. Breedlove 60775 ( CAS) ; 12 April 1931, 36 miles southeast of Rosario , I. L. Wiggins 5301 ( CAS, TEX-LL) ; 14 April 1931, Between Laguna Catavina and Laguna Seca Chapala, I. L. Wiggins 5341 ( CAS, NY) ; 31 May 1965, En el alto Arroyo Alfredo al noroeste de la ex misión Santa María, R. Moran 12180 ( CAS, SD) ; 24 March 1962, North San Lorenzo Island, called Isla Partida, actually middle of three islands in the group, Gulf of California , I. L. Wiggins 17261 ( CAS) ; 11 March 1999, 1 km al N de Cataviña sobre la carretera a Tijuana, J. L. Panero 7406, B. Crozier, S. González, J. I. Calzada ( IEB, NY, TEX-LL) ; 30 May 1973, In wash, 10 mi S of El Marmol, I. L. Wiggins 4377 ( NY) ; 18 March 2002, Near Rancho Santa Ynes, A. L. Reina G. 2002-230, T. R. Van Devender, M. A. Dimmitt, J. F. Wiens, C. Martin ( USON) ; 12 April 2002, Misión de Santa Maria , M. Salazar 647 ( SD) ; 27 March 1991, 2 millas al NO de San Agustín , G. L. Webster 28605 ( SD) ; 23 March 1973, 1.0 milla al norte de San Roques, G. L. Webster 18094, G. L. Webster 18094, S. Lynch ( SD) ; 14 April 1954, Catavina , D. R. Harvey s.n. ( SD) ; 15 March 1947, El aguila, C. F. Harbison 41544 ( SD) ; 25 September 1965, Lavado de arena, San Agustín , B. F. Howe s.n. ( SD) ; 22 March 1951, 2.0 millas al norte de Catavina, Brattstrom s.n. ( SD) ; 18 April 1992, Rocky hills and granitic bolder fields at arroyo Cataviña , at Santa Ines, M. Merello, D. Brunner 284 ( MEXU) ; 13 December 1977, 39 miles south of El Rosario, 3 miles south of Santa Cecilia on Mex Hwy 1. B. C. Norte, K. C. Nixon, K. C. Nixon, C. P. Cowan 826 ( MEXU) ; 10 April 1952, 2 to 3 miles north of San Fernando, H. S: Gentry 11677, W. B. Fox 11677 ( MEXU) .

Figures

FIGURE 13. Map showing the distribution of Astragalus hypoleucus, A. hypoxylus, and A. idrietorun in Mexico.